Set sub-ruby BUNDLE_GEMFILE sooner.  Invoke 'bundle install' directly rather than via 'system'.
Remove extraneous 'puts'.
Use env var to set Rails' relative url root as it seems more robust across versions.
Add integration test for Rails 3.1.
Make Rubylet::Environment extend Hash to conform to Rack SPEC.
Set binmode and ASCII_8BIT encoding on the input stream to comply with Rack::Lint.
Merge pull request #1 from pmahoney/master

More tests, Lint