render_tag -> tag: final block

Summary:
Convert a final few `render_tag()` calls to `tag()` calls. This leaves us with 36 calls:

  - 9 are in Conpherence, and will be converted after merging. Using Views makes the most sense here, to get access to renderHTMLView() and such.
  - 2 are the definition and its library map entry.
  - 3 are in the documentation.
  - I believe the remaining 22 are too difficult to convert pre-merge. About half are in code which is slated for destruction; the other half are in the base implementations of very common classes (like PhabricatorStandardPageView) and can only be converted by converting the entire codebase.

My plan at this point is:

  - Test the branch thoroughly.
  - Merge to master.
  - Over time, resolve the remaining issues: lint means things shouldn't get any worse.

Test Plan: See inlines.

Reviewers: vrana

Reviewed By: vrana

CC: aran, edward

Maniphest Tasks: T2432

Differential Revision: https://secure.phabricator.com/D4802