Clean up file browse view a bit

Summary:

• Use DiffusionCommitQuery
• Get rid of the "Author" column.
• Collapse commit + revision together.
• Better tooltips to cover for the removed information.
• Colorize only the "line" column.
• Generally, reduce the amount of visual noise and non-code-stuff going on in this interface.
• I'd like to make the "<<" thing look nicer too but that might take some actual design.

Test Plan: See screenshots.

Reviewers: btrahan, chad

Reviewed By: chad

CC: chad, aran

Differential Revision: https://secure.phabricator.com/D7457