Remove ManiphestTaskListController

Summary:
Fixes T3273. Fixes T3088. Fixes T2992. Fixes T1163. Fixes T1008. Ref T3241. Ref T1386. Ref T418. Ref T2625. Ref T603.

Replaces task list with one powered by ApplicationSearch.

Test Plan:
After many days of work, the task search interface now looks exactly the same as it did before.

{F58114}

Reviewers: btrahan

Reviewed By: btrahan

CC: aran, chad

Maniphest Tasks: T418, T603, T1008, T1163, T1386, T2625, T2992, T3088, T3241, T3273

Differential Revision: https://secure.phabricator.com/D6979