Adding paging to transcript pages

Summary:
enable paging by adding a AphrontPagerView to the two
transcript page.

Test Plan:
test the paging on both pages. Also test it with a certain
phid is given.

Reviewed By: epriestley
Reviewers: epriestley, tuomaspelkonen
CC: epriestley, jungejason
Differential Revision: 116