WIP: Creates commit component

What does this MR do?

Creates a reusable component in vue for the commit column in CI tables. Props are based both on:

• app/views/projects/deployments/_commit.html.haml,
• app/views/projects/ci/pipelines/_pipeline.html.haml
• New data that will be sent in the API response: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7174

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

Tests are still missing. We could find a better way to include SVGs.

Why was this MR needed?

There is some shared code between Pipelines, Environments and Deployments table. In Environments and deployments table we were already using an haml partial. The commit column from this 3 different tables has exactly the same information.

In order to accomplish new features like folders in Environments !7015 (merged) and real time updates in Pipelines !7196 (merged) without duplicating the code we need to create a vue component that renders the needed information.

This component was written in vue 2 having in mind it will only be merged after !7254 (merged)

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• CHANGELOG entry added
• Documentation created/updated
• API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

It will be used in: #22539 (closed) #5983 (closed)