FIltering by commit message on the compare revisions page
### Problem to solve
Filtering by commit message, to find special commits on compare revisions page
### Intended users
Release Manager, Devloper - to find related to issue commits in release changelog (as example when compare specific build tags after release)
### Further details
Such filter is available at now on commits view page
### Proposal
Integrate live search input in the commits header block on compare revisions page (Projects::CompareController::show) as on committs page (Projects::CommitController::show)
### Permissions and Security
It is covered by page access security rules
### Documentation
Actualy it is native understandable non critical feature
### Testing
Maybe there is needed same tests as in Projects::CommitController::show if they represented
### What does success look like, and how can we measure that?
The commits on the revisions compare page must be correclty filtered by commit message on user input
### Links / references
- [Compare revisions page](https://gitlab.com/gitlab-org/gitlab-ce/compare/10-2-stable...master)
- [Commits page](https://gitlab.com/gitlab-org/gitlab-ce/commits/master)
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