FEATURE: QA-3541 - more logging
FEATURE: QA-3541 - synchronised access to project pull requests
FEATURE: QA-3541 - set response status explicitly
CONFIG: QA-3541 - change some defaults
FEATURE: QA-3541 - use automanaged repsitory cache for triggering builds instead of listing all projects every time when notification arrives
Merge pull request #4 from pgressa/master

Improvements for GitHub push model - logging + cache