Show warning when build is pending and there are not runners

This change is based on: !1530 (merged).

This resolves #2967 (closed).

Please review @dzaporozhets @vsizov

mentioned in issue #2967 (closed)

Added 2 commits:

• 4bf69b0b - Fix feature tests
• 485f6e49 - Show warning if build doesn't have runners with specified tags or runners didn't connect recently

Added 1 commit:

• f36884a4 - Fix specs

Added 32 commits:

• f36884a4...e3edd53a - 30 commits from branch master
• 2bb8dec2 - Show warning if build doesn't have runners with specified tags or runners didn't connect recently
• aef9184a - Fix specs

@vsizov Can you review once again?

Looks good to me

This is how it looks

Any advice for texts: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/1573/diffs#e754d40b6756dc7da1dfef93124be8dfcde2342e_42_42?

Added 1 commit:

• b9f7719c - Fix warning sign

Added 26 commits:

• b9f7719c...3b93d37e - 23 commits from branch master
• 22e424e1 - Show warning if build doesn't have runners with specified tags or runners didn't connect recently
• f0bb7169 - Fix specs
• e8552028 - Fix warning sign

Added 6 commits:

• e8552028...2d0fcb4d - 3 commits from branch master
• 7af4f521 - Show warning if build doesn't have runners with specified tags or runners didn't connect recently
• 16bfd9d3 - Fix specs
• d9e2232f - Fix warning sign

Status changed to merged

mentioned in commit a3a80eac