Fix nix.rb issue
Fix nix.rb issue

Curl gives this warning with 739b37caf8b312a62b254e551cd4760f3e6de697,

Warning: .curlrc:1: warning: '-sS' uses unquoted white space in 
Warning: the line that may cause side-effects!

Hadn't realized there was a special syntax for curlrc. It needs everything on a separate line.

Apologies for the mistake!
Thanks
andyli/travis-build,andyli/travis-build,craigcitro/travis-build,craigcitro/travis-build