.travis.yml: De-activate OSX job
.travis.yml: De-activate OSX job

Travis OSX queue has had 1300+ jobs backed up for many
hours now.

Fixes https://github.com/coala/coala/issues/3611

JohnS-01/coala,kartikeys98/coala,SanketDG/coala,refeed/coala,arush0311/coala,impmihai/coala,yashtrivedi96/coala,Balaji2198/coala,arush0311/coala,refeed/coala,damngamerz/coala,ayushin78/coala,shreyans800755/coala,impmihai/coala,Shade5/coala,yashLadha/coala,rimacone/testing2,Asalle/coala,damngamerz/coala,ayushin78/coala,Balaji2198/coala,NiklasMM/coala,jayvdb/coala,yashtrivedi96/coala,damngamerz/coala,yashLadha/coala,RJ722/coala,karansingh1559/coala,Asnelchristian/coala,netman92/coala,coala/coala,karansingh1559/coala,Shade5/coala,NiklasMM/coala,arjunsinghy96/coala,SanketDG/coala,jayvdb/coala,nemaniarjun/coala,CruiseDevice/coala,coala/coala,meetmangukiya/coala,SanketDG/coala,sagark123/coala,kartikeys98/coala,coala/coala,arush0311/coala,CruiseDevice/coala,meetmangukiya/coala,incorrectusername/coala,yashtrivedi96/coala,netman92/coala,Nosferatul/coala,Balaji2198/coala,Nosferatul/coala,CruiseDevice/coala,nemaniarjun/coala,sagark123/coala,arjunsinghy96/coala,coala-analyzer/coala,Shade5/coala,karansingh1559/coala,impmihai/coala,NiklasMM/coala,aptrishu/coala,MariosPanag/coala,rimacone/testing2,kartikeys98/coala,aptrishu/coala,incorrectusername/coala,meetmangukiya/coala,RJ722/coala,sagark123/coala,jayvdb/coala,Asnelchristian/coala,arjunsinghy96/coala,incorrectusername/coala,JohnS-01/coala,JohnS-01/coala,Nosferatul/coala,Asalle/coala,aptrishu/coala,shreyans800755/coala,MariosPanag/coala,Asnelchristian/coala,MariosPanag/coala,refeed/coala,RJ722/coala,netman92/coala,nemaniarjun/coala,coala-analyzer/coala,Asalle/coala,rimacone/testing2,yashLadha/coala,ayushin78/coala,shreyans800755/coala,coala-analyzer/coala