Jenkins doesn't do a very good job with identifying what has been changed.
While it has a syntax to defined patterns, it compares the current build with the previous build (in case of git-verify it can be a totally different branch) instead of checking the HEAD commit.
This patch introduces shell scripts to do this better:
* It doesn't depend on Jenkins any more
* It can be executed locally
* It can detect web changes properly (see the relation change as an example).
Change-Id: I9d37775e3818c08c4aa96ffb78f84d57f28a2c95
