Adds a 'known issue' for the .astropy permissions issue.  Fixes #988.
Adds a 'known issue' for the .astropy permissions issue.  Fixes #988.

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