utils/check_patch.py: Speed and memory usage improvements

Turns out we had a bug in the code that verified whether
a file was tracked by git. With the bug fixed, a lot less
files will be scanned. Moreover, expand the list of
blacklisted extensions and paths, making it faster to
check the tree, even if you have logs in it.

Also, instead of creating multiple file checker
objects, that will be stored in memory, refactor
the existing one to process several files and
use it. This greatly saves memory.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Merge branch 'master' into 0.15
autotest-db-delete-job: use settings instance instead of module

This is a fix for a condition that was most certainly introduced
during the global_config -> settings API change.

Signed-off-by: Cleber Rosa <crosa@redhat.com>
gitignore: added the auto generated tko protocol buffer module

Signed-off-by: Cleber Rosa <crosa@redhat.com>
Merge branch 'master' into 0.15