Move Maniphest list rendering to SearchEngine

Summary: Ref T4986. Moves Maniphest over. Nothing tricky here, just a complex block of rendering.

Test Plan: Viewed Maniphest list. Created Maniphest panel. Used batch editor, drag-and-drop.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T4986

Differential Revision: https://secure.phabricator.com/D9139