tests: run cppcheck for PR in Travis
tests: run cppcheck for PR in Travis

Failures are ignored for now.

jremmert-phytec-iot/RIOT,Darredevil/RIOT,adjih/RIOT,watr-li/RIOT,JensErdmann/RIOT,Darredevil/RIOT,rousselk/RIOT,Lexandro92/RIOT-CoAP,OlegHahm/RIOT,rakendrathapa/RIOT,robixnai/RIOT,koenning/RIOT,mfrey/RIOT,rfswarm/RIOT,marcosalm/RIOT,asanka-code/RIOT,chris-wood/RIOT,ximus/RIOT,brettswann/RIOT,PSHIVANI/Riot-Code,rajma996/RIOT,chris-wood/RIOT,dailab/RIOT,cladmi/RIOT,luciotorre/RIOT,rousselk/RIOT,alignan/RIOT,fnack/RIOT,smlng/RIOT,gbarnett/RIOT,binarylemon/RIOT,LudwigKnuepfer/RIOT,brettswann/RIOT,khhhh/RIOT,EmuxEvans/RIOT,l3nko/RIOT,jfischer-phytec-iot/RIOT,gbarnett/RIOT,yogo1212/RIOT,watr-li/RIOT,stevenj/RIOT,gebart/RIOT,rfuentess/RIOT,adjih/RIOT,herrfz/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,rakendrathapa/RIOT,cladmi/RIOT,OTAkeys/RIOT,koenning/RIOT,syin2/RIOT,dhruvvyas90/RIOT,msolters/RIOT,Osblouf/RIOT,sgso/RIOT,automote/RIOT,jfischer-phytec-iot/RIOT,kaspar030/RIOT,latsku/RIOT,gebart/RIOT,MonsterCode8000/RIOT,beurdouche/RIOT,miri64/RIOT,x3ro/RIOT,herrfz/RIOT-old,kYc0o/RIOT,Lotterleben/RIOT,Darredevil/RIOT,kb2ma/RIOT,openkosmosorg/RIOT,watr-li/RIOT,plushvoxel/RIOT,kushalsingh007/RIOT,biboc/RIOT,1blankz7/RIOT,Osblouf/RIOT,ximus/RIOT,patkan/RIOT,avmelnikoff/RIOT,MarkXYang/RIOT,josephnoir/RIOT,lebrush/RIOT,thiagohd/RIOT,authmillenon/RIOT,beurdouche/RIOT,centurysys/RIOT,latsku/RIOT,dhruvvyas90/RIOT,emmanuelsearch/RIOT,msolters/RIOT,Josar/RIOT,neumodisch/RIOT,beurdouche/RIOT,kushalsingh007/RIOT,tfar/RIOT,DipSwitch/RIOT,locicontrols/RIOT,haoyangyu/RIOT,AnonMall/RIOT,kaleb-himes/RIOT,sumanpanchal/RIOT,robixnai/RIOT,avmelnikoff/RIOT,ks156/RIOT,ThanhVic/RIOT,l3nko/RIOT,bartfaizoltan/RIOT,watr-li/RIOT,Ell-i/RIOT,emmanuelsearch/RIOT,MohmadAyman/RIOT,rajma996/RIOT,dhruvvyas90/RIOT,rfswarm2/RIOT,katezilla/RIOT,EmuxEvans/RIOT,Yonezawa-T2/RIOT,tdautc19841202/RIOT,mziegert/RIOT,kushalsingh007/RIOT,avmelnikoff/RIOT,roberthartung/RIOT,mziegert/RIOT,cladmi/RIOT,neumodisch/RIOT,abp719/RIOT,Lexandro92/RIOT-CoAP,AnonMall/RIOT,jremmert-phytec-iot/RIOT,LudwigKnuepfer/RIOT,haoyangyu/RIOT,Hyungsin/RIOT-OS,OlegHahm/RIOT,rakendrathapa/RIOT,kbumsik/RIOT,d00616/RIOT,fnack/RIOT,yogo1212/RIOT,adjih/RIOT,plushvoxel/RIOT,daniel-k/RIOT,bartfaizoltan/RIOT,marcosalm/RIOT,plushvoxel/RIOT,d00616/RIOT,jferreir/RIOT,RubikonAlpha/RIOT,TobiasFredersdorf/RIOT,altairpearl/RIOT,toonst/RIOT,yogo1212/RIOT,Darredevil/RIOT,altairpearl/RIOT,stevenj/RIOT,herrfz/RIOT-old,abkam07/RIOT,neumodisch/RIOT,toonst/RIOT,patkan/RIOT,ximus/RIOT,jbeyerstedt/RIOT-OTA-update,bartfaizoltan/RIOT,rajma996/RIOT,locicontrols/RIOT,brettswann/RIOT,ant9000/RIOT,dkm/RIOT,lebrush/RIOT,OTAkeys/RIOT,centurysys/RIOT,PSHIVANI/Riot-Code,phiros/RIOT,RubikonAlpha/RIOT,gautric/RIOT,ant9000/RIOT,Osblouf/RIOT,LudwigKnuepfer/RIOT,roberthartung/RIOT,abkam07/RIOT,benoit-canet/RIOT,rfuentess/RIOT,wentaoshang/RIOT,luciotorre/RIOT,binarylemon/RIOT,toonst/RIOT,malosek/RIOT,kaleb-himes/RIOT,rousselk/RIOT,bartfaizoltan/RIOT,RIOT-OS/RIOT,khhhh/RIOT,Hyungsin/RIOT-OS,koenning/RIOT,thomaseichinger/RIOT,ntrtrung/RIOT,herrfz/RIOT,tdautc19841202/RIOT,OlegHahm/RIOT,daniel-k/RIOT,authmillenon/RIOT,phiros/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,kb2ma/RIOT,openkosmosorg/RIOT,emmanuelsearch/RIOT,LudwigOrtmann/RIOT,Lotterleben/RIOT,rousselk/RIOT,immesys/RiSyn,MohmadAyman/RIOT,neiljay/RIOT,tdautc19841202/RIOT,sumanpanchal/RIOT,alex1818/RIOT,smlng/RIOT,centurysys/RIOT,binarylemon/RIOT,daniel-k/RIOT,jbeyerstedt/RIOT-OTA-update,kYc0o/RIOT,tfar/RIOT,Hyungsin/RIOT-OS,alignan/RIOT,aeneby/RIOT,openkosmosorg/RIOT,sgso/RIOT,alex1818/RIOT,gautric/RIOT,gautric/RIOT,binarylemon/RIOT,alex1818/RIOT,jhollister/RIOT,jasonatran/RIOT,locicontrols/RIOT,MohmadAyman/RIOT,jremmert-phytec-iot/RIOT,kaspar030/RIOT,backenklee/RIOT,jhollister/RIOT,BytesGalore/RIOT,dailab/RIOT,1blankz7/RIOT,OTAkeys/RIOT,zhuoshuguo/RIOT,aeneby/RIOT,FrancescoErmini/RIOT,attdona/RIOT,Hyungsin/RIOT-OS,emmanuelsearch/RIOT,ks156/RIOT,l3nko/RIOT,kYc0o/RIOT,syin2/RIOT,biboc/RIOT,rfswarm/RIOT,PSHIVANI/Riot-Code,OlegHahm/RIOT,smlng/RIOT,TobiasFredersdorf/RIOT,centurysys/RIOT,MonsterCode8000/RIOT,watr-li/RIOT,LudwigOrtmann/RIOT,malosek/RIOT,thiagohd/RIOT,MarkXYang/RIOT,Yonezawa-T2/RIOT,ximus/RIOT,binarylemon/RIOT,MarkXYang/RIOT,shady33/RIOT,khhhh/RIOT,LudwigOrtmann/RIOT,Yonezawa-T2/RIOT,khhhh/RIOT,zhuoshuguo/RIOT,rakendrathapa/RIOT,ant9000/RIOT,rfuentess/RIOT,changbiao/RIOT,cladmi/RIOT,sgso/RIOT,fnack/RIOT,miri64/RIOT,dkm/RIOT,nsol-nmsu/RIOT,abkam07/RIOT,JensErdmann/RIOT,avmelnikoff/RIOT,automote/RIOT,rajma996/RIOT,ntrtrung/RIOT,A-Paul/RIOT,LudwigOrtmann/RIOT,yogo1212/RIOT,kb2ma/RIOT,jfischer-phytec-iot/RIOT,Yonezawa-T2/RIOT,Yonezawa-T2/RIOT,benoit-canet/RIOT,mfrey/RIOT,Lotterleben/RIOT,mziegert/RIOT,Lotterleben/RIOT,immesys/RiSyn,adrianghc/RIOT,kbumsik/RIOT,immesys/RiSyn,katezilla/RIOT,sgso/RIOT,jferreir/RIOT,jasonatran/RIOT,AnonMall/RIOT,ant9000/RIOT,RubikonAlpha/RIOT,neumodisch/RIOT,benoit-canet/RIOT,BytesGalore/RIOT,asanka-code/RIOT,changbiao/RIOT,sumanpanchal/RIOT,herrfz/RIOT,kaspar030/RIOT,arvindpdmn/RIOT,kerneltask/RIOT,rfswarm2/RIOT,kYc0o/RIOT,DipSwitch/RIOT,MonsterCode8000/RIOT,herrfz/RIOT,roberthartung/RIOT,JensErdmann/RIOT,josephnoir/RIOT,khhhh/RIOT,zhuoshuguo/RIOT,adrianghc/RIOT,centurysys/RIOT,gautric/RIOT,miri64/RIOT,RubikonAlpha/RIOT,mtausig/RIOT,altairpearl/RIOT,LudwigKnuepfer/RIOT,automote/RIOT,basilfx/RIOT,adrianghc/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,mziegert/RIOT,kYc0o/RIOT,rfswarm/RIOT,rfswarm2/RIOT,LudwigOrtmann/RIOT,RubikonAlpha/RIOT,sgso/RIOT,Lotterleben/RIOT,Ell-i/RIOT,kaspar030/RIOT,OTAkeys/RIOT,abp719/RIOT,ant9000/RIOT,RIOT-OS/RIOT,neumodisch/RIOT,ks156/RIOT,MonsterCode8000/RIOT,abkam07/RIOT,mziegert/RIOT,malosek/RIOT,MohmadAyman/RIOT,jhollister/RIOT,katezilla/RIOT,EmuxEvans/RIOT,latsku/RIOT,1blankz7/RIOT,x3ro/RIOT,dailab/RIOT,mfrey/RIOT,tdautc19841202/RIOT,rakendrathapa/RIOT,wentaoshang/RIOT,1blankz7/RIOT,MarkXYang/RIOT,luciotorre/RIOT,BytesGalore/RIOT,Lexandro92/RIOT-CoAP,PSHIVANI/Riot-Code,TobiasFredersdorf/RIOT,zhuoshuguo/RIOT,x3ro/RIOT,nsol-nmsu/RIOT,AnonMall/RIOT,neiljay/RIOT,herrfz/RIOT-old,sumanpanchal/RIOT,mtausig/RIOT,alignan/RIOT,changbiao/RIOT,d00616/RIOT,LudwigOrtmann/RIOT,Josar/RIOT,chris-wood/RIOT,thiagohd/RIOT,changbiao/RIOT,josephnoir/RIOT,MarkXYang/RIOT,PSHIVANI/Riot-Code,altairpearl/RIOT,Osblouf/RIOT,syin2/RIOT,MohmadAyman/RIOT,immesys/RiSyn,wentaoshang/RIOT,luciotorre/RIOT,gebart/RIOT,kaleb-himes/RIOT,gebart/RIOT,basilfx/RIOT,biboc/RIOT,herrfz/RIOT-old,hamilton-mote/RIOT-OS,rajma996/RIOT,changbiao/RIOT,JensErdmann/RIOT,phiros/RIOT,kerneltask/RIOT,kb2ma/RIOT,hamilton-mote/RIOT-OS,jremmert-phytec-iot/RIOT,sumanpanchal/RIOT,locicontrols/RIOT,RBartz/RIOT,patkan/RIOT,AnonMall/RIOT,RIOT-OS/RIOT,thiagohd/RIOT,herrfz/RIOT-old,foss-for-synopsys-dwc-arc-processors/RIOT,rfswarm2/RIOT,biboc/RIOT,nsol-nmsu/RIOT,shady33/RIOT,latsku/RIOT,locicontrols/RIOT,dhruvvyas90/RIOT,shady33/RIOT,RBartz/RIOT,d00616/RIOT,miri64/RIOT,lebrush/RIOT,jfischer-phytec-iot/RIOT,shady33/RIOT,DipSwitch/RIOT,lebrush/RIOT,rfswarm/RIOT,openkosmosorg/RIOT,attdona/RIOT,d00616/RIOT,basilfx/RIOT,tdautc19841202/RIOT,alex1818/RIOT,nsol-nmsu/RIOT,altairpearl/RIOT,centurysys/RIOT,ThanhVic/RIOT,kaleb-himes/RIOT,authmillenon/RIOT,kaspar030/RIOT,wentaoshang/RIOT,lazytech-org/RIOT,dhruvvyas90/RIOT,benoit-canet/RIOT,tfar/RIOT,RBartz/RIOT,hamilton-mote/RIOT-OS,benoit-canet/RIOT,yogo1212/RIOT,dailab/RIOT,arvindpdmn/RIOT,watr-li/RIOT,altairpearl/RIOT,Darredevil/RIOT,rfuentess/RIOT,gbarnett/RIOT,marcosalm/RIOT,AnonMall/RIOT,mtausig/RIOT,haoyangyu/RIOT,thomaseichinger/RIOT,mtausig/RIOT,herrfz/RIOT,automote/RIOT,kerneltask/RIOT,Osblouf/RIOT,1blankz7/RIOT,1blankz7/RIOT,mfrey/RIOT,lazytech-org/RIOT,FrancescoErmini/RIOT,basilfx/RIOT,dhruvvyas90/RIOT,l3nko/RIOT,jhollister/RIOT,RIOT-OS/RIOT,rfswarm2/RIOT,gbarnett/RIOT,lebrush/RIOT,luciotorre/RIOT,asanka-code/RIOT,immesys/RiSyn,Lotterleben/RIOT,LudwigKnuepfer/RIOT,chris-wood/RIOT,EmuxEvans/RIOT,neumodisch/RIOT,gbarnett/RIOT,backenklee/RIOT,Ell-i/RIOT,phiros/RIOT,rfuentess/RIOT,ks156/RIOT,daniel-k/RIOT,alignan/RIOT,brettswann/RIOT,EmuxEvans/RIOT,Lexandro92/RIOT-CoAP,DipSwitch/RIOT,luciotorre/RIOT,TobiasFredersdorf/RIOT,zhuoshuguo/RIOT,mziegert/RIOT,patkan/RIOT,alex1818/RIOT,thiagohd/RIOT,haoyangyu/RIOT,authmillenon/RIOT,roberthartung/RIOT,yogo1212/RIOT,haoyangyu/RIOT,msolters/RIOT,binarylemon/RIOT,jferreir/RIOT,hamilton-mote/RIOT-OS,toonst/RIOT,attdona/RIOT,fnack/RIOT,kaleb-himes/RIOT,Josar/RIOT,ntrtrung/RIOT,MarkXYang/RIOT,syin2/RIOT,robixnai/RIOT,authmillenon/RIOT,tdautc19841202/RIOT,RIOT-OS/RIOT,lebrush/RIOT,gbarnett/RIOT,kushalsingh007/RIOT,marcosalm/RIOT,changbiao/RIOT,arvindpdmn/RIOT,malosek/RIOT,ThanhVic/RIOT,sumanpanchal/RIOT,d00616/RIOT,kbumsik/RIOT,Lotterleben/RIOT,jferreir/RIOT,kbumsik/RIOT,msolters/RIOT,tfar/RIOT,josephnoir/RIOT,l3nko/RIOT,nsol-nmsu/RIOT,jbeyerstedt/RIOT-OTA-update,abp719/RIOT,abp719/RIOT,chris-wood/RIOT,aeneby/RIOT,katezilla/RIOT,jasonatran/RIOT,jbeyerstedt/RIOT-OTA-update,MonsterCode8000/RIOT,jfischer-phytec-iot/RIOT,BytesGalore/RIOT,daniel-k/RIOT,mfrey/RIOT,msolters/RIOT,neiljay/RIOT,jasonatran/RIOT,katezilla/RIOT,shady33/RIOT,FrancescoErmini/RIOT,josephnoir/RIOT,lazytech-org/RIOT,hamilton-mote/RIOT-OS,stevenj/RIOT,cladmi/RIOT,daniel-k/RIOT,robixnai/RIOT,backenklee/RIOT,zhuoshuguo/RIOT,Ell-i/RIOT,wentaoshang/RIOT,robixnai/RIOT,openkosmosorg/RIOT,phiros/RIOT,smlng/RIOT,abkam07/RIOT,lazytech-org/RIOT,tfar/RIOT,EmuxEvans/RIOT,attdona/RIOT,mtausig/RIOT,gebart/RIOT,ThanhVic/RIOT,jhollister/RIOT,kerneltask/RIOT,attdona/RIOT,Darredevil/RIOT,RBartz/RIOT,A-Paul/RIOT,l3nko/RIOT,bartfaizoltan/RIOT,miri64/RIOT,emmanuelsearch/RIOT,FrancescoErmini/RIOT,TobiasFredersdorf/RIOT,immesys/RiSyn,dkm/RIOT,JensErdmann/RIOT,alex1818/RIOT,Lexandro92/RIOT-CoAP,Osblouf/RIOT,roberthartung/RIOT,beurdouche/RIOT,ntrtrung/RIOT,robixnai/RIOT,abkam07/RIOT,koenning/RIOT,stevenj/RIOT,stevenj/RIOT,arvindpdmn/RIOT,dkm/RIOT,OTAkeys/RIOT,DipSwitch/RIOT,fnack/RIOT,asanka-code/RIOT,A-Paul/RIOT,thomaseichinger/RIOT,MohmadAyman/RIOT,neiljay/RIOT,jferreir/RIOT,smlng/RIOT,chris-wood/RIOT,DipSwitch/RIOT,stevenj/RIOT,thiagohd/RIOT,beurdouche/RIOT,arvindpdmn/RIOT,adrianghc/RIOT,wentaoshang/RIOT,A-Paul/RIOT,shady33/RIOT,biboc/RIOT,ximus/RIOT,patkan/RIOT,rfswarm/RIOT,rousselk/RIOT,authmillenon/RIOT,alignan/RIOT,automote/RIOT,RubikonAlpha/RIOT,bartfaizoltan/RIOT,jhollister/RIOT,RBartz/RIOT,fnack/RIOT,FrancescoErmini/RIOT,aeneby/RIOT,x3ro/RIOT,basilfx/RIOT,patkan/RIOT,Josar/RIOT,automote/RIOT,locicontrols/RIOT,BytesGalore/RIOT,kbumsik/RIOT,aeneby/RIOT,neiljay/RIOT,arvindpdmn/RIOT,ThanhVic/RIOT,dkm/RIOT,jferreir/RIOT,gautric/RIOT,attdona/RIOT,MonsterCode8000/RIOT,PSHIVANI/Riot-Code,backenklee/RIOT,phiros/RIOT,kushalsingh007/RIOT,brettswann/RIOT,rakendrathapa/RIOT,kb2ma/RIOT,RBartz/RIOT,plushvoxel/RIOT,koenning/RIOT,sgso/RIOT,rfswarm/RIOT,herrfz/RIOT,koenning/RIOT,thomaseichinger/RIOT,msolters/RIOT,jbeyerstedt/RIOT-OTA-update,syin2/RIOT,ks156/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,ThanhVic/RIOT,brettswann/RIOT,Lexandro92/RIOT-CoAP,Josar/RIOT,kerneltask/RIOT,ntrtrung/RIOT,thomaseichinger/RIOT,adjih/RIOT,malosek/RIOT,asanka-code/RIOT,Ell-i/RIOT,benoit-canet/RIOT,jremmert-phytec-iot/RIOT,jremmert-phytec-iot/RIOT,A-Paul/RIOT,asanka-code/RIOT,openkosmosorg/RIOT,Yonezawa-T2/RIOT,FrancescoErmini/RIOT,jasonatran/RIOT,abp719/RIOT,dailab/RIOT,marcosalm/RIOT,ximus/RIOT,ntrtrung/RIOT,JensErdmann/RIOT,abp719/RIOT,rousselk/RIOT,malosek/RIOT,latsku/RIOT,latsku/RIOT,marcosalm/RIOT,adrianghc/RIOT,plushvoxel/RIOT,adjih/RIOT,avmelnikoff/RIOT,kushalsingh007/RIOT,Hyungsin/RIOT-OS,haoyangyu/RIOT,locicontrols/RIOT,x3ro/RIOT,rfswarm2/RIOT,backenklee/RIOT,OlegHahm/RIOT,khhhh/RIOT,rajma996/RIOT,emmanuelsearch/RIOT,lazytech-org/RIOT,toonst/RIOT