Don't claim that we proxy chunked content, we don't

The Pivotal API now returns transfer-encoding: chunked, but by the time we proxy the data back to the browser the content is actually no longer chunked.  So we filter out that header and the app works again.
We don't need the debugger gem, there's hardly any ruby
Remove proxy.rb from the public lib folder
Merge pull request #12 from unboxed/fix-chunked-encoding

Fix chunked encoding