#435: display statistics by commits
Fixed: RecordNotUnique in Issue#set_serial_id
rollback changes
#435: Added extra condition according to Alexander's comments
Merge pull request #438 from abf/rosa-build:435-statistics-by-commits
 #435: Commits statistics
#435: display statistics by issues and pull-requests
#435: added filter by users and groups
#435: cleanup
#435: added reopen status for issues
#435: rollback some changes
#435: added specs for Statistic
#435: updated fillColor for ChartJS
Merge pull request #439 from abf/rosa-build:435-statistics-by-issues
 #435: Issues && PullRequests statistics
Updated regex for BuildList#prepare_extra_params