Add script to check Signed-off-by header in patches

Signed-off-by: Michal Čihař <mcihar@suse.cz>
Check Signed-off-by in pull requests

Signed-off-by: Michal Čihař <mcihar@suse.cz>
Better way to discover new commits

Signed-off-by: Michal Čihař <mcihar@suse.cz>
Merge commit 'a21a18cf562925e256aa780024bc3674001ffcd3'
Merge commit '7109d49bfa6f1c1c10c1667d39bd1cdc5e980b3d'
Merge branch 'QA_4_1'
Translated using Weblate (Korean)

Currently translated at 71.1% (1950 of 2742)
Merge remote-tracking branch 'origin/QA_4_1' into QA_4_1
Merge branch 'master' of github.com:phpmyadmin/phpmyadmin
Merge remote-tracking branch 'origin/QA_4_1'