gcoap: fix resource separator inserting
gcoap: fix resource separator inserting

kerneltask/RIOT,lazytech-org/RIOT,adrianghc/RIOT,adrianghc/RIOT,roberthartung/RIOT,kaspar030/RIOT,RIOT-OS/RIOT,OlegHahm/RIOT,RIOT-OS/RIOT,x3ro/RIOT,beurdouche/RIOT,authmillenon/RIOT,gebart/RIOT,RIOT-OS/RIOT,OTAkeys/RIOT,lazytech-org/RIOT,rfuentess/RIOT,authmillenon/RIOT,josephnoir/RIOT,miri64/RIOT,basilfx/RIOT,neiljay/RIOT,yogo1212/RIOT,rfuentess/RIOT,immesys/RiSyn,Josar/RIOT,miri64/RIOT,josephnoir/RIOT,kYc0o/RIOT,mfrey/RIOT,ant9000/RIOT,miri64/RIOT,toonst/RIOT,toonst/RIOT,hamilton-mote/RIOT-OS,immesys/RiSyn,smlng/RIOT,kYc0o/RIOT,mtausig/RIOT,roberthartung/RIOT,avmelnikoff/RIOT,cladmi/RIOT,OTAkeys/RIOT,kerneltask/RIOT,miri64/RIOT,Josar/RIOT,BytesGalore/RIOT,mfrey/RIOT,Josar/RIOT,ant9000/RIOT,ant9000/RIOT,beurdouche/RIOT,gebart/RIOT,neiljay/RIOT,BytesGalore/RIOT,hamilton-mote/RIOT-OS,avmelnikoff/RIOT,LudwigKnuepfer/RIOT,toonst/RIOT,rfuentess/RIOT,rfuentess/RIOT,aeneby/RIOT,mtausig/RIOT,josephnoir/RIOT,x3ro/RIOT,kaspar030/RIOT,avmelnikoff/RIOT,Josar/RIOT,ks156/RIOT,mtausig/RIOT,kaspar030/RIOT,LudwigOrtmann/RIOT,smlng/RIOT,adrianghc/RIOT,neiljay/RIOT,LudwigOrtmann/RIOT,OTAkeys/RIOT,neiljay/RIOT,x3ro/RIOT,kerneltask/RIOT,biboc/RIOT,neiljay/RIOT,cladmi/RIOT,josephnoir/RIOT,x3ro/RIOT,kYc0o/RIOT,RIOT-OS/RIOT,jasonatran/RIOT,authmillenon/RIOT,yogo1212/RIOT,roberthartung/RIOT,hamilton-mote/RIOT-OS,beurdouche/RIOT,ks156/RIOT,kbumsik/RIOT,adjih/RIOT,adrianghc/RIOT,A-Paul/RIOT,kbumsik/RIOT,biboc/RIOT,Josar/RIOT,basilfx/RIOT,yogo1212/RIOT,OlegHahm/RIOT,authmillenon/RIOT,gebart/RIOT,RIOT-OS/RIOT,kYc0o/RIOT,yogo1212/RIOT,basilfx/RIOT,OlegHahm/RIOT,LudwigOrtmann/RIOT,authmillenon/RIOT,lazytech-org/RIOT,mtausig/RIOT,kbumsik/RIOT,kaspar030/RIOT,mfrey/RIOT,toonst/RIOT,cladmi/RIOT,jasonatran/RIOT,yogo1212/RIOT,adjih/RIOT,ant9000/RIOT,lazytech-org/RIOT,aeneby/RIOT,ks156/RIOT,smlng/RIOT,LudwigKnuepfer/RIOT,BytesGalore/RIOT,authmillenon/RIOT,x3ro/RIOT,mtausig/RIOT,OTAkeys/RIOT,roberthartung/RIOT,BytesGalore/RIOT,smlng/RIOT,biboc/RIOT,aeneby/RIOT,BytesGalore/RIOT,adrianghc/RIOT,kaspar030/RIOT,adjih/RIOT,basilfx/RIOT,LudwigKnuepfer/RIOT,beurdouche/RIOT,LudwigOrtmann/RIOT,kYc0o/RIOT,toonst/RIOT,aeneby/RIOT,hamilton-mote/RIOT-OS,cladmi/RIOT,adjih/RIOT,OlegHahm/RIOT,LudwigKnuepfer/RIOT,josephnoir/RIOT,immesys/RiSyn,avmelnikoff/RIOT,LudwigOrtmann/RIOT,immesys/RiSyn,ks156/RIOT,mfrey/RIOT,rfuentess/RIOT,OTAkeys/RIOT,kbumsik/RIOT,A-Paul/RIOT,mfrey/RIOT,kerneltask/RIOT,lazytech-org/RIOT,A-Paul/RIOT,A-Paul/RIOT,hamilton-mote/RIOT-OS,biboc/RIOT,immesys/RiSyn,jasonatran/RIOT,biboc/RIOT,jasonatran/RIOT,ant9000/RIOT,A-Paul/RIOT,avmelnikoff/RIOT,immesys/RiSyn,yogo1212/RIOT,jasonatran/RIOT,LudwigOrtmann/RIOT,gebart/RIOT,gebart/RIOT,smlng/RIOT,aeneby/RIOT,miri64/RIOT,adjih/RIOT,kbumsik/RIOT,OlegHahm/RIOT,beurdouche/RIOT,LudwigKnuepfer/RIOT,basilfx/RIOT,cladmi/RIOT,kerneltask/RIOT,roberthartung/RIOT,ks156/RIOT