Provide RUBY_VERSION for cached-bundle
Add Makefile for building and testing

Advantages over scripts in `script/`:

- Works without gopath
- Works without godep
Make the cucumber test suite work against gh

gh should be compiled and named `./hub` in the project root
Ensure that test server always responds with valid JSON

Even for blank responses, 404s and error pages. Otherwise Sawyer chokes.
Respect $HTTP_PROXY even in test mode

Go otherwise respects HTTP_PROXY environment variables by default, but
special-cases requests made to "localhost" or 127.0.0.1 by disabling
proxy for them, which makes me a sad panda since I want to debug the
requests hub makes to our local test server.

https://code.google.com/p/go/source/browse/src/pkg/net/http/transport.go?name=go1.2#544
https://code.google.com/p/go/issues/detail?id=7256

This un-fucks ProxyFromEnvironment by reimplementing it without the
bizarre limitation.
Temporary switch to `gh.protocol/gh.host` git config

We should come back to supporting the old hub-prefixed config options, though.