1. Allow entering any branch name for a protected branch.
- Either pick from a list of options, or enter it manually
- You can enter wildcards.
2. Display branches matching a protected branch.
- Add a `ProtectedBranches#show` page that displays the branches
matching the given protected branch, or a message if there are no
matches.
- On the `index` page, display the last commit for an exact match,
or the number of matching branches for a wildcard match.
- Add an `iid` column to `protected_branches` - this is what we use for
the `show` page URL.
- On the off chance that this feature is unnecessary, this commit
encapsulates it neatly, so it can be removed without affecting
anything else.
3. Remove the "Last Commit" column from the list of protected branches.
- There's no way to pull these for wildcard protected branches, so it's
best left for the `show` page.
- Rename the `@branches` instance variable to `@protected_branches`
- Minor styling changes with the "Unprotect" button - floated right
like the "Revoke" button for personal access tokens
4. Paginate the list of protected branches.
5. Move the instructions to the left side of the page.
