Use timeline view in Differential and make inlines somewhat usable again

Summary:
Ref T2222. This gets rid of Differential's custom view and uses a standard view instead.

This also mostly fixes the rendering logic for inlines.

This is headed to the `tmp.differential` branch.

Test Plan: {F112696}

Reviewers: btrahan

Reviewed By: btrahan

CC: chad, aran

Maniphest Tasks: T1790, T2222

Differential Revision: https://secure.phabricator.com/D8215
Fix double-rendering of inline comments in mail

Summary: Ref T2222. This is a `tmp.differential`-only issue. Inline comment transactions now have content, so we treat them like body text. We also render them separately as inline text. This produces mail where inlines are rendered twice.

Test Plan: Sent myself mail, saw only one copy of inlines.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2222

Differential Revision: https://secure.phabricator.com/D8216
Make Asana bridge work with new Differential transactions

Summary: Ref T2222. Unbreak the Asana/JIRA bridge.

Test Plan: {F112712}

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2222

Differential Revision: https://secure.phabricator.com/D8217
Add some missing text for Differential inline transactions

Summary: Ref T2222. Add inline and default text.

Test Plan: Feed works again.

Reviewers: chad, btrahan

Reviewed By: chad

CC: aran

Maniphest Tasks: T2222

Differential Revision: https://secure.phabricator.com/D8218