Maniphest Detail view for mobile.

Summary: I try to access tasks a lot on my phone, but its hard to parse. I'm sure most of this will get tossed with new transactions, but wanted to land it anyways.

Test Plan: Test ticket details on iOS simulator and Chrome.

Reviewers: epriestley, btrahan

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D4619