[Redesign] PHUIPagerView

Summary: Ref T8099, Moves AphrontPagerView to PHUIPagerView, converts to standard PHUIButtons and adds some additional features for icon placement on buttons.

Test Plan: Tested Advanced Search and Searching files in Diffusion. Works as expected.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T8342, T8099

Differential Revision: https://secure.phabricator.com/D13092