adding Gemfile*
Add cleanup tasks
bench depends on app generation
add Roda benchmark that delegates to sub apps
Remove Gemfile.lock

Shipping a Gemfile makes sense so people can easily install the
dependencies.  However, I don't think we should should a lock file,
as the code should work with multiple versions of the dependencies
(or be updated so it does).
Since bench task depends on apps, don't need to run apps separately