Fix every HTML issue I could find

Summary:
I attempted to test every interface. I probably missed some stuff, but I at least have some level of confidence that the phutil_tag branch is fairly stable.

Fixed these issues:

[1] Fixed a Herald issue with object links in transcripts. Some actions return
links; this was previously hard-coded.
[2] DarkConsole refactoring created an issue where the "`" event handler registered too many times.
[3] Fixed a bug where strlen($value) was being checked, but fields may now return array(). Possibly we should implement phutil_is_empty_html() or similar.
[4] Fixed a undefined variable issue for image edit transactions.
[5] Fixed an issue with rendering participant transactions. This required phutil_safe_html() because pht() can't handle array() for %s.
[6] Fixed an issue where feed was entirely overescaped by reverting an overly ambitious render_tag -> tag.
[7] Fixed an issue with strict tables and inserting '' instead of 0 into an integer column.
[8] Fixed an issue where • was shown escaped.
[9] Fixed an issue where "no data" was overescaped.
[10] Fixed an issue with strict tables and inserting '' instead of 0 into an integer column.
[11] Fixed an issue with strict tables and inserting ''.
[12] Fixed an issue with missing space after ":" for mini panels.

Encountered (but did not fix) these issues:

[X1] "e" works incorrectly on comments you are not allowed to edit. Did not fix.
[X2] Coverage currently interacts incorrectly with "--everything" for Phutil tests.

Test Plan:

• Viewed Differential.
• Created a diff via copy/paste.
• Viewed standalone diff.
• Jumped to diff via changeset table.
• Created a revision.
• Updated revision.
• Added a comment.
• Edited revision dependencies.
• Edited revision tasks.
• Viewed MetaMTA transcripts.
• Viewed Herald transcripts [1].
• Downloaded raw diff.
• Flagged / unflagged revision.
• Added/edited/deleted inline comment.
• Collapsed/expanded file.
• Did show raw left.
• Did show raw right.
• Checked previews for available actions.
• Clicked remarkup buttons
• Used filetree view.
• Used keyboard: F, j, k, J, K, n, p, t, h, "?" [2] [X1].
• Created a meme.
• Uploaded a file via drag and drop.
• Viewed a revision with no reviewers.
• Viewed a revision with >100 files.
• Viewed various other revisions [3].
• Viewed an image diff.
• Added image diff inline comments.
• Viewed Maniphest.
• Ran various queries.
• Created task.
• Created similar task.
• Added comments to tasks.
• Ran custom query.
• Saved custom query.
• Edited custom queries.
• Drag-reordered tasks.
• Batch edited tasks.
• Exported tasks to excel.
• Looked at reports (issue in T2311 notwithstanding).
• Viewed Diffusion.
• Browsed Git, SVN, HG repositories.
• Looked at history, browse, change, commit views.
• Viewed audit.
• Performed various audit searches.
• Viewed Paste.
• Performed paste searches.
• Created, edited, forked paste.
• Viewed Phriction.
• Edited a page.
• Viewed edit history.
• Used search typeahead to search for user / application.
• Used search to search for text.
• Viewed Phame.
• Viewed Blog, Post.
• Viewed live post.
• Published/unpublished post.
• Previewed post.
• Viewed Pholio.
• Edited/commented mock.
• Viewed ponder.
• Viewed question.
• Added answer/comment.
• Viewed Diviner.
• Viewed Conpherence [4] [5].
• Made Conpherence updates.
• Viewed calendar.
• Created status.
• Viewed status.
• Viewed Feed [6].
• Viewed Projects.
• Viewed project detail.
• Edited project.
• Viewed Owners.
• Viewed package detail.
• Edited package [7].
• Viewed flags.
• Edited flag.
• Deleted flag.
• Viewed Herald.
• Viewed rules.
• Created rule.
• Edited rule.
• Viewed edit log.
• Viewed transcripts.
• Inspected a transcript.
• Viewed People.
• Viewed list.
• Administrated user.
• Checked username/delete stuff.
• Looked at create/import LDAP/activity logs.
• Looked at a user profile.
• Looked at user about page.
• Looked at Repositories.
• Edited repository.
• Edited arcanist project.
• Looked at daemons.
• Looked at all daemons [8].
• Viewed combined log.
• Looked at configuration.
• Edited configuration.
• Looked at setup issues [9].
• Looked at current settings.
• Looked at application list.
• Installed / uninstalled applications [10].
• Looked at mailing lists.
• Created a mailing list.
• Edited a mailing list.
• Looked at sent mail.
• Looked at received mail.
• Looked at send/receive tests.
• Looked at settings.
• Clicked through all the panels.
• Looked at slowvote.
• Created a slowvote [11].
• Voted in a slowvote.
• Looked at Macro.
• Created a macro.
• Edited a macro.
• Commented on a macro.
• Looked at Countdown.
• Created a Countdown.
• Looked at it.
• Looked at Drydock.
• Poked around a bit.
• Looked at Fact.
• Poked around a bit.
• Looked at files.
• Looked at a file.
• Uploaded a file.
• Looked at Conduit.
• Made a Conduit call.
• Looked at UIExamples.
• Looked at PHPAST.
• Looked at PHIDs.
• Looked at notification menu.
• Looked at notification detail.
• Logged out.
• Logged in.
• Looked at homepage [12].
• Ran arc unit --everything --no-coverage [X2].

Reviewers: vrana, btrahan

Reviewed By: vrana

CC: aran

Maniphest Tasks: T2432

Differential Revision: https://secure.phabricator.com/D4807