fixes #46
Merge pull request #47 from bacongobbler/master

remove bpwatch hack
Add image tagging support
Merge pull request #49 from opdemand/tagging

Add optional image tagging support
fix broken python buildpack by generating a random request id used by bpwatch instrumentation
Merge pull request #51 from opdemand/pythonfix

Generate request ID for broken python buildpack
pass bin/release $build_root instead of $app_root

Needed by heroku-buildpack-ruby
Merge pull request #56 from icco/patch-1

pass bin/release $build_root instead of $app_root
comprehend buildpack urls with treeish components