Fix fork counter ui bug for safari
## What does this MR do?
Fixes UI bug on safari when fork button has blue arrow
## Screenshots

See merge request !4221
Allows MR authors to have the source branch removed when merging the MR
closes#13191
The location of the checkbox might not be optimal so any feedback is welcome. Any other feedback too obviously.
Screenshot:

See merge request !2801
Resolve "Wrong sorting of commit order in MR view?"
!4052 fixed this for the most obvious cases, but there were still some problems.
Here's my test case: I have a branch where I was suffering from an unfortunate
issue. Every other commit I made had its commit date set to one day before it
should have been. (Perhaps my system clock was misbehaving.)
```shell
for i in {1..10}
do
echo $i > $i
git add $i
GIT_COMMITTER_DATE=`date -v -$((i % 2))d` git commit -m $i
done
```
The git CLI still gives me the commits in the right order, but I can see that
the timestamps alternate between two values:
```shell
$ git log --format='%h %ct %p %s' master...HEAD
f0c3108 1463646313 3d38a13 10
3d38a13 1463559913 67f419b 9
67f419b 1463646313 74330c0 8
74330c0 1463559913 56361d7 7
56361d7 1463646313 ba1b60c 6
ba1b60c 1463559913 f91497d 5
f91497d 1463646313 79c5e57 4
79c5e57 1463559913 b953cef 3
b953cef 1463646313 12fc411 2
12fc411 1463559913 835715b 1
```
Unfortunately, GitLab didn't like this _at all_. Here's what the commits on my
MR from that branch looked like:

That's because we were sorting the commits by date, which is safe if they are in
that order anyway. If they aren't, then because Ruby's sorting isn't stable, we
lose even the ordering among the correctly-ordered commits with the same
timestamp.
After these changes (and reloading the MR's diff), this looks like:

The commits view was also wrong, but in a slightly different way. In table form:
| View | Before | After |
| --- | --- | --- |
| Commit list | 10, 8, 6, 4, 2, 9, 7, 5, 3, 1 | 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 |
| MR commits | 10, 2, 8, 4, 6, 5, 7, 3, 9, 1 | 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 |
Closes#12724
See merge request !4208
Fixed project settings alert colors
In another MR, the class name was changed making all the alert messages have no background color

See merge request !4161
It's possible to construct a commit graph where the output of `git log`
isn't in timestamp order. Grouping the commits in the list by date then
gives dramatically wrong results. Instead, go for the more pragmatic
approach: use the commits in the order they're given, and just show the
date line each time the date changes. This means that the same date
header can show up multiple times, but at least the ordering is
preserved.
Add container registry support
Tasks:
- [x] Merge docker/distribution authentication service: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/3787
- [x] Implement Docker Registry API
- [x] Show a list of docker images in GitLab
- [x] Remove registry repository on project deletion
- [x] Support project rename, move and namespace rename
- [x] Use token when connecting the registry
- [x] Allow to delete images from GitLab
- [x] Support pushing from GitLab CI (gitlab-ci-token / $CI_BUILD_TOKEN)
- [x] Support GitLab Runner pulling for public repositories
- [ ] Support GitLab Runner pulling for private repositories
- [x] Add tests for Docker Registry API
- [x] Add tests for a views
- [x] Make texts nicer
- [x] Implement a backup support
- [ ] Create administration documentation https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/4141
- [ ] Create user documentation
See merge request !4040
Added authentication service for docker registry
This adds a simple authentication service for docker which uses current user credentials to authenticate pulls and pushes.
I have only one concern. Since the `.docker/config` is unencrypted, thus the password for user stored there is unencrypted, maybe we should from the start implement function to generate/provide a separate password just for the purposes of accessing docker registry?
What do you think @jacobvosmaer @sytses @marin?
cc @marin
See merge request !3787