Add support for cross project references for labels
## Summary
Support for cross project references for labels.
## Rationale
1. Cross project label references are currently not supported in GitLab
1. `to_reference` method signature in `Label` model breaks the abstraction introduced in `Referable`.
`concerns/referable.rb: def to_reference(_from_project = nil)`
Signatures:
```
label.rb: def to_reference(format = :id)
commit_range.rb: def to_reference(from_project = nil)
commit.rb: def to_reference(from_project = nil)
external_issue.rb: def to_reference(_from_project = nil)
group.rb: def to_reference(_from_project = nil)
issue.rb: def to_reference(from_project = nil)
merge_request.rb: def to_reference(from_project = nil)
milestone.rb: def to_reference(from_project = nil)
project.rb: def to_reference(_from_project = nil)
snippet.rb: def to_reference(from_project = nil)
user.rb: def to_reference(_from_project = nil)
```
This MR suggests using `def to_reference(from_project = nil, format: :id)` which makes use of keyword arguments and preserves abstract interface.
1. We need support for cross project label references when we want to move issue to another project
It may happen that issue description, system notes or comments contain reference to label and this reference will be invalid after moving issue to another project and will not be displayed correctly unless we have support for cross project references.
Merge request that needs this feature: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/2831
I think that cross project label references may be useful, (example: `Hey, see our issues for CI in GitLab CE! - gitab-org/gitlab-ce~"CI"`).
cc @JobV @DouweM @rspeicher
See merge request !2966
Updated SAML and Omniauth docs
Updated SAML and Omniauth docs with information on the new behavior recently introduced in !2882
/cc @ernstvn @DouweM
See merge request !2950
Branded appearance to CE
Closes#11489
The difference with the EE version is only that there is no distinction between light and dark logos, though this wasn't used anyway. If this is fine, I'll create a MR on EE too.
TODO:
- [x] Copy docs
- [x] Make new screenshots
- [ ] Remove Custom Welcome message feature?
@rymai: I was unsure what labels to add to ping you, so I just ping you like this 😉
/cc @DouweM
See merge request !2927
The only major difference with the EE version is the change from a light and dark logo to only a header logo
The dark logo wasn't used anyway, so it seemed to make sense to me to rename the field to the actual function of it
Reformats confusing '[named here]' section for 3rd party code attribution
Weird formatting originally. Which of the following is the proper format for attribution?
1. Submitted on behalf of a third-party: [David Alexander]
1. Submitted on behalf of a third-party: [[] David Alexander]
1. Submitted on behalf of a third-party: [] David Alexander
1. Submitted on behalf of a third-party: [[ David Alexander ]]
1. ... _etc._
With this change, it allows for either of the following formats:
1. Submitted on behalf of a third-party: [David Alexander]
1. Submitted on behalf of a third-party: David Alexander
See merge request !2861
Add instructions for pushing tags as well as branches
Current instructions will push the svn branches but not tags - add missing line to tags
See merge request !2778
Fixed ~git beeing displayed as link to issues tagged with git in architecture.md
The architecture documentation explains `~git` from the picture below which is replaced by a [link to issues tagged with `git`](https://gitlab.com/gitlab-org/gitlab-ce/issues?label_name=git). I believe that this was unintended and should be fixed by using backticks.

See merge request !2814
Introduce API for serving the artifacts archive
Add API to download build artifacts archive in context of GitLab API
/cc @DouweM @grzesiek
See merge request !2893