Add date range filtering for activity, push, and pull logs
Summary: Ref T13049. This is just a general nice-to-have so you don't have to export a 300MB file if you want to check the last month of data or whatever.
Test Plan: Applied filters to all three logs, got appropriate date-range result sets.
Reviewers: amckinley
Reviewed By: amckinley
Maniphest Tasks: T13049
Differential Revision: https://secure.phabricator.com/D18970