Fix repository page ui issues

## What does this MR do?

Fixes 3 UI issues outlined in https://gitlab.com/gitlab-org/gitlab-ce/issues/19610. 

## Are there points in the code the reviewer needs to double check?

Not afaik. 

## Why was this MR needed?

To fix problems with the UI noted in relevant issues.

## What are the relevant issue numbers?

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/19610 (combines all three) also

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/19614, Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/19615, Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/19616

Integrates changes from: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5530/diffs?view=parallel

## Screenshots (if relevant)

Right align & color contrast issues (https://gitlab.com/gitlab-org/gitlab-ce/issues/19614 & https://gitlab.com/gitlab-org/gitlab-ce/issues/19616)

Before: 

![no-contrast](/uploads/9dec2510250806434cf686d6362eda4d/Screen_Shot_2016-07-07_at_1.46.08_PM.png)
![left-align](/uploads/09ddc525491010538d7bce95c410a067/Screen_Shot_2016-07-07_at_1.42.17_PM.png)

After: 

![right-align-and-contrast](/uploads/0d303179150ce718a28cd38ddbbf2954/right-align-and-contrast.png)

Truncate last commit (https://gitlab.com/gitlab-org/gitlab-ce/issues/19615)

Before: 
![not-truncated](/uploads/e66213db28d11cc44e7eb8578ac788fd/Screen_Shot_2016-07-07_at_1.40.26_PM.png)
After: 

![truncated-commit-message](/uploads/94947234451f29c34df3c2bd8846193d/truncated-commit-message.png)


**UPDATED screenshot![Screen_Shot_2016-09-02_at_2.15.04_PM](/uploads/dc11e6159759818b5ea69e04206c5691/Screen_Shot_2016-09-02_at_2.15.04_PM.png)**

## Does this MR meet the acceptance criteria?

- [X] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [X] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [X] API support added
- Tests
  - [X] Added for this feature/bug
  - [X] All builds are passing
- [X] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [X] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [X] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5308