Setup Pre-Commit build for gora-trunk Jenkins job

hsaputra mentioned [0] on the dev@ list about shadowing a Pre-commit build for gora-trunk.
Basically this would be really useful to automatically apply new patches to the source tree in order to give feedback to the contributor on things that can be fixed prior to a committer looking at the patch. For example, some projects may not accept a patch if it does not come with unit tests, etc.

This issue will address the above brief.

[0] http://www.mail-archive.com/dev%40gora.apache.org/msg03742.html