Force travis to use sphinx v1.1.3
Force travis to use sphinx v1.1.3

Closes #934

saimn/astropy,lpsinger/astropy,pllim/astropy,astropy/astropy,larrybradley/astropy,aleksandr-bakanov/astropy,joergdietrich/astropy,lpsinger/astropy,AustereCuriosity/astropy,astropy/astropy,kelle/astropy,DougBurke/astropy,saimn/astropy,dhomeier/astropy,stargaser/astropy,DougBurke/astropy,joergdietrich/astropy,kelle/astropy,MSeifert04/astropy,StuartLittlefair/astropy,saimn/astropy,mhvk/astropy,funbaker/astropy,dhomeier/astropy,astropy/astropy,kelle/astropy,joergdietrich/astropy,bsipocz/astropy,tbabej/astropy,lpsinger/astropy,DougBurke/astropy,stargaser/astropy,larrybradley/astropy,lpsinger/astropy,mhvk/astropy,pllim/astropy,pllim/astropy,larrybradley/astropy,funbaker/astropy,dhomeier/astropy,MSeifert04/astropy,kelle/astropy,mhvk/astropy,tbabej/astropy,AustereCuriosity/astropy,joergdietrich/astropy,astropy/astropy,DougBurke/astropy,pllim/astropy,dhomeier/astropy,StuartLittlefair/astropy,bsipocz/astropy,StuartLittlefair/astropy,astropy/astropy,pllim/astropy,dhomeier/astropy,lpsinger/astropy,MSeifert04/astropy,saimn/astropy,stargaser/astropy,AustereCuriosity/astropy,aleksandr-bakanov/astropy,tbabej/astropy,mhvk/astropy,tbabej/astropy,aleksandr-bakanov/astropy,AustereCuriosity/astropy,joergdietrich/astropy,AustereCuriosity/astropy,bsipocz/astropy,StuartLittlefair/astropy,funbaker/astropy,funbaker/astropy,tbabej/astropy,bsipocz/astropy,mhvk/astropy,StuartLittlefair/astropy,kelle/astropy,saimn/astropy,MSeifert04/astropy,larrybradley/astropy,larrybradley/astropy,aleksandr-bakanov/astropy,stargaser/astropy