Summary:
Depends on D20530. Ref T13291. When users paste links to files in Diffusion into remarkup contexts, identify them and specialize the rendering.
When the URIs are embedded with `{...}`, parse them in more detail.
This is a lead-up to a `{src ...}` rule which will use the same `View` but give users more options to customize presentation.
Test Plan: {F6463580}
Reviewers: amckinley
Reviewed By: amckinley
Maniphest Tasks: T13291
Differential Revision: https://secure.phabricator.com/D20538
