rake_task: add verbose option to reduce logging

Signed-off-by: Pierre-Alexandre Meyer <pierre@mouraf.org>
rake_task: make package smaller

Don't bundle development dependencies, test files, binaries, etc.
in the generated package - we won't use them.

Signed-off-by: Pierre-Alexandre Meyer <pierre@mouraf.org>
rake_task: add support for :path in Gemfile

Signed-off-by: Pierre-Alexandre Meyer <pierre@mouraf.org>
Merge branch 'master' of github.com:killbill/killbill-plugin-framework-ruby