Move Dashboard and Panel edit history out of the way

Summary: Fixes T5170, Create new page for dashboard history

Test Plan: Open dashboard, manage dashboard, click on "View History". Dashboard history should appear. Panel history should appear on panel view page under panel.

Reviewers: epriestley, Blessed Reviewers

Reviewed By: epriestley, Blessed Reviewers

Subscribers: epriestley, Korvin

Maniphest Tasks: T5170

Differential Revision: https://secure.phabricator.com/D9280