[close #247] bundle platform with user env args
setup GEM_PATH so rubygems can find bundler
remove bundler setup since it affects BundlerWrapper tests
don't overwrite travis's PATH

the PATH matters b/c the binstubs pick up the ruby based on the ruby in
the path: `#!/usr/bin/env ruby`.
git add . is weird on travis
preserve RUBYOPT except for BundlerWrapper tests
Merge pull request #254 from heroku/schneems/fix-platform-env-arg

[close #247] bundle platform with user env args
remove debug test output
fix ruby patchlevel support
Merge pull request #268 from heroku/schneems/patchlevel

Fix patchlevel support
bump to v118
changelog
[ci skip] fix date
temporarily disable default-cache
bump to v119
changelog
fix sublime text highlighting
default cache test turned off until further notice
Merge branch 'master' of git://github.com/heroku/heroku-buildpack-ruby into upstream-merge

* 'master' of git://github.com/heroku/heroku-buildpack-ruby:
  default cache test turned off until further notice
  fix sublime text highlighting
  changelog
  bump to v119
  temporarily disable default-cache
  [ci skip] fix date
  changelog
  bump to v118
  fix ruby patchlevel support
  remove debug test output
  preserve RUBYOPT except for BundlerWrapper tests
  git add . is weird on travis
  don't overwrite travis's PATH
  remove bundler setup since it affects BundlerWrapper tests
  setup GEM_PATH so rubygems can find bundler
  [close #247] bundle platform with user env args