Added ruby syntax validation. Uses default system ruby.
Added ruby syntax validation. Uses default system ruby.

benesch/sublime-linter,zenlambda/SublimeLinter3,SublimeLinter/SublimeLinter-for-ST2,biodamasceno/SublimeLinter-for-ST2,biodamasceno/SublimeLinter-for-ST2,ikappas/SublimeLinter3,SublimeLinter/SublimeLinter-for-ST2,ikappas/SublimeLinter3,lunixbochs/sublimelint,SublimeLinter/SublimeLinter3,simonzack/SublimeLinter3,uschmidt83/SublimeLinter-for-ST2,paulirish/SublimeLinter3,tangledhelix/SublimeLinter-for-ST2,Raynos/SublimeLinter3-raynos,jasonrhaas/SublimeLinter3,SublimeLinter/SublimeLinter3,paulirish/SublimeLinter3,jasonrhaas/SublimeLinter3,zenlambda/SublimeLinter3,lunixbochs/sublimelint,simonzack/SublimeLinter3,uschmidt83/SublimeLinter-for-ST2,smanolloff/SublimeLinter3,tangledhelix/SublimeLinter-for-ST2,smanolloff/SublimeLinter3,benesch/sublime-linter