Merge branch 'issue_12758' into 'master'
Implement custom notification level options ![Screen_Shot_2016-06-17_at_15.31.43](/uploads/3fc47d2f461b3e8b67bb8acaa304cf99/Screen_Shot_2016-06-17_at_15.31.43.png) ![Screenshot_from_2016-06-15_10-52-27](/uploads/88dbdd21d97e80ee772fe08fa0c9b393/Screenshot_from_2016-06-15_10-52-27.png) part of #12758 See merge request !4389
Showing
![doc/workflow/notifications/settings.png](https://lab.nexedi.cn/kirr/gitlab-ce/-/raw/0d21f8c3982e99f7851f7615b6c816086fbf441f/doc/workflow/notifications/settings.png)