Update .travis.yml to test os MacOS as well as Linux
Update .travis.yml to test os MacOS as well as Linux

gfldex/doc,jonathanstowe/doc,stmuk/doc,MasterDuke17/doc,jonathanstowe/doc,MasterDuke17/doc,dmaestro/doc,antquinonez/doc,jonathanstowe/doc,MasterDuke17/doc,perl6/doc,stmuk/doc,dmaestro/doc,jonathanstowe/doc,antquinonez/doc,dmaestro/doc,dmaestro/doc,stmuk/doc,perl6/doc,antquinonez/doc,tbrowder/doc,tbrowder/doc,antquinonez/doc,tbrowder/doc,gfldex/doc,tbrowder/doc,MasterDuke17/doc,gfldex/doc,perl6/doc,stmuk/doc,perl6/doc,antquinonez/doc,gfldex/doc,stmuk/doc,gfldex/doc,perl6/doc,jonathanstowe/doc,dmaestro/doc