Support referencing issues to a project whose name starts with a digit
Gitlab supports adding users or projects whose name starts with a "_" or a digit, but the regexp in markdown.rb enforces "a-zA-Z" for the first character.
This change allows to reference issues or merge requests in other projects whose name starts with a digit, like `owner/2ndtestproject#123` or `2nduser/superproject!123`.
See merge request !264
Fix protected branches routing
### Summary
On the master branch, if you attempt to access the protected branches in the project settings with an empty repo, you get `NoMethodError - undefined method "project_url"`.
### Steps to reproduce
1. Check out GitLab master and run.
2. Create a new project.
3. Go to Settings.
4. Click on "Protected branches"
### Expected behavior
The controller is supposed to redirect back to the projects page since there are no branches.
### Observed behavior
Internal Error 500
### Relevant logs
```
NoMethodError - undefined method `project_url' for #<Projects::ProtectedBranchesController:0x007fd920054af0>:
app/controllers/application_controller.rb:157:in `method_missing'
actionpack (4.1.9) lib/action_dispatch/routing/polymorphic_routes.rb:142:in `polymorphic_url'
actionpack (4.1.9) lib/action_dispatch/routing/url_for.rb:161:in `url_for'
actionpack (4.1.9) lib/action_controller/metal/redirecting.rb:91:in `_compute_redirect_to_location'
turbolinks (2.0.0) lib/turbolinks.rb:15:in `_compute_redirect_to_location_with_xhr_referer'
actionpack (4.1.9) lib/action_controller/metal/redirecting.rb:71:in `redirect_to
```
### Fix
I added a unit test for the empty project case and replicated the issue. I added the URL router helpers that appear to be necessary after 42387b733b.
See merge request !359
Include number of affected people in all/group mention autocomplete item.
As mentioned in #2054.
To minimize misuse of all/group mentions, the autocomplete title includes the number of members this mention will notify, so users will be more considerate what groups they mention.
Example:
at-all "**all** All Project and Group Members (12)"
at-gitlab "**gitlab** GitLab (12)"
See merge request !1596
Filter icons look like proper buttons
The filter icons (Push events, Merge events, Comments, Team) now have a border
that signifies they can be pushed. This not only keeps it in line with the rest
of the application buttons, but it makes it more obvious, especially for the
Merge events button with a checkbox icon.
Fixes#1993
See merge request !1576
Fixes grammatical consistency and small changes
This commit adds consistency to small things like periods, commas,
and gives additional information to buttons and headers, etc.
Fixes#2002, #2005, #2003.
See merge request !1570
Dmitriy Zaporozhets
Dmitriy Zaporozhets
Marin Jankovski
Nicolas Bouilleaud
Stan Hu
Robert Schilling
Jeroen van Baarsen
sue445
Douwe Maan
Sytse Sijbrandij
Sabba Petri
Mlanawo Mbechezi
Marin Jankovski
Job van der Voort
Jacob Vosmaer