This change converts the CommitView class to TypeScript, and replaces

various UI elements with Ink. In particular:

Several icons have been switched from fontawesome to Tabler icons

  bundled in Ink.
The progress spinner when creating a post-commit review request now

  uses <Ink.Spinner>.
The confirmation dialog uses <Ink.Dialog>

This also fixes a couple ugly interaction issues relating to what is

happening when during the event handler. The big problem was that we

were always creating the confirmation dialog and then handling other

cases in the confirm handler. This meant that for commits that had an

existing review request, we'd prompt them to create a new review request

and then just open the existing one. For inaccessible commits, we'd

prompt them and then do nothing. These conditions are now checked at the

top of the click handler, so we don't prompt the user unless we really

need to.

Ran js-tests.
Created new review requests for commits and saw that the interaction

  worked correctly for both confirm and cancel.
Clicked on commits with existing review requests and saw that the page

  linked directly without any prompt.
Verified the appearance of the new icons and spinner.