Gracefully handle missing config file
Gracefully handle missing config file

https://circleci.com/gh/atom/atom/7630

stinsonga/atom,PKRoma/atom,brettle/atom,PKRoma/atom,stinsonga/atom,atom/atom,Mokolea/atom,Mokolea/atom,liuderchi/atom,liuderchi/atom,t9md/atom,t9md/atom,andrewleverette/atom,andrewleverette/atom,stinsonga/atom,brettle/atom,atom/atom,brettle/atom,liuderchi/atom,PKRoma/atom,Mokolea/atom,stinsonga/atom,andrewleverette/atom,t9md/atom,liuderchi/atom,atom/atom