Swap Maniphest edit writes to new transactions

Summary: Ref T2217. This is essentially the last writer, should be able to start deleting code now.

Test Plan: Used "Edit Task" to make a bunch of task edits.

Reviewers: btrahan, garoevans

Reviewed By: garoevans

CC: aran

Maniphest Tasks: T2217

Differential Revision: https://secure.phabricator.com/D7090
Gut ManiphestTransactionEditor

Summary:
Ref T2217. Removes most of the code from ManiphestTransactionEditor.

  - Provides mail tag support in ManiphestTransactionEditorPro.
  - There was one more write (subscribe/unsubscribe button) that I'd missed; modernize that.

Test Plan:
  - Clicked subscribe/unsubscribe.
  - Made some edits, verified mail had appropriate mail tags.

Reviewers: btrahan, garoevans

Reviewed By: garoevans

CC: aran

Maniphest Tasks: T2217

Differential Revision: https://secure.phabricator.com/D7091
Minor, sneak in one fix from future Maniphest patches ahead of review

Summary: I goofed this constant when defining mail tags.

Auditors: btrahan
ObjectHeader Status icons

Summary: Adds status icons and colors to Maniphest and Differential. Also minor tweaks to them in hovercards. Probably some other stuff too.

Test Plan: Test many diff and task states.

Reviewers: epriestley, btrahan

Reviewed By: epriestley

CC: Korvin, aran

Differential Revision: https://secure.phabricator.com/D7098
Fix `differential.getdiff`, etc., for diffs with no Arcanist Project

Summary:
`getArcanistProjectName()` has some logic which gets messy with the `self::ATTACHABLE` mechanism. This makes `differential.getdiff` and similar Conduit methods throw an exception when querying a diff which doesn't have a project. See <http://pastebin.com/Czzrd0Jz>.

Instead, unconditionally attach a project (possibly `null`) when loading diffs if they need projects.

Test Plan: Ran `differential.getdiff` against a `arc diff --raw` diff with no project, got a result instead of an exception.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran, sttwister

Differential Revision: https://secure.phabricator.com/D7101
Remove ManiphestTransaction

Summary: Ref T2217. The preview had the last callsite, nuke it.

Test Plan: Used preview. Grepped for `ManiphestTransaction(`, `ManiphestTransaction::`, `'ManiphestTransaction'`, `"ManiphestTransaction"`.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2217

Differential Revision: https://secure.phabricator.com/D7092
Rename ManiphestTransactionPro -> ManiphestTransaction

Summary: Ref T2217. Pro is the new standard.

Test Plan: Lots of `grep`, made a pile of Maniphest views/edits.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2217

Differential Revision: https://secure.phabricator.com/D7093
Rename "transactionpro" table to "transaction"

Summary: Ref T2217. Cleans up the table names. Moves old data to `maniphest_transaction_legacy`. We'll drop that eventually once it's more clear that I didn't break the world.

Test Plan: Did reads/writes to/from these tables.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2217

Differential Revision: https://secure.phabricator.com/D7094
Smooth "no effect" detection in Maniphest for @mentions

Summary:
Ref T2217. Since we aren't actually using subscriptions yet, the "transactions have no effect" detection can trigger for `@mention`s of users who are already CC'd on a task.

Be more conservative about generating a CC transaction.

Test Plan: See screenshot.

Reviewers: btrahan, chad

Reviewed By: chad

CC: chad, aran

Maniphest Tasks: T2217

Differential Revision: https://secure.phabricator.com/D7095
Improve some new string translations

Summary: Ref T2217. Cleans up some of the "attached %d file(s)" stuff.

Test Plan: Generated some of these transactions and verified they render more naturally.

Reviewers: btrahan, chad

Reviewed By: chad

CC: aran

Maniphest Tasks: T2217

Differential Revision: https://secure.phabricator.com/D7096
Further smooth "Add CC" interaction in Maniphest

Summary: Ref T2217. Fixes T3877. Improves more behaviors in the presence of "no effect" detection and new comment storage.

Test Plan: Added CCs, added existing CCs, implicitly added CCs via reassign, added CCs with comment.

Reviewers: btrahan, garoevans

Reviewed By: garoevans

CC: aran

Maniphest Tasks: T2217, T3877

Differential Revision: https://secure.phabricator.com/D7100
Reduce Maniphest fulltext limit from PHP_INT_MAX to 10k

Summary:
PHP_INT_MAX is rejected by ElasticSearch since it's outside of the representable integer range (see: <https://gist.github.com/JustinTulloss/c4ac0e1c93d6d1e91744>).

Just use 10K, as matching more than 10K results probably isn't useful to anyone.

Test Plan: Confirmed this fixes the issue in IRC. Ran a fulltext search.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Differential Revision: https://secure.phabricator.com/D7097
Fix "edit" for Maniphest comments

Summary:
Ref T2217. Fixes T3876. We incorrectly have a unique key on `(authorPHID, transactionPHID)`, which prevents saving multiple versions of a comment.

I'm not entirely sure why this exists. I think it came from Pholio (where it works for inlines, because it has an additional component, but maybe should be adjusted) but we might need to wipe it out of more apps too.

Test Plan: Edited a comment in Maniphest.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2217, T3876

Differential Revision: https://secure.phabricator.com/D7102
Render Maniphest custom fields last

Summary: Ref T2217. Fixes T3865. Eventually we'll probably make more of this configurable, but for now shove custom fields down instead of sort of arbitrarily putting them in the middle.

Test Plan: Looked at a task with attached revisions and custom fields, saw custom fields last.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2217, T3865

Differential Revision: https://secure.phabricator.com/D7103
Make standard fields more liberal about interpreting empty strings

Summary:
Fixes T3867. We currently show more empty custom field values on task detail pages than we should, for at least two reasons:

  - `<select />` fields with an empty string option store `""`, but users reasonably expect this to mean "no value".
  - Old fields may have stored empty strings, and migrated forward.

This fix generally aligns behavior with user expectations. We could get more extreme about not storing `""` in the database, but I think this is generally a less surpsing fix.

Test Plan: Made a select with a `"" : "None"` option, selected it, saw it vanish from task detail screen.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T3867

Differential Revision: https://secure.phabricator.com/D7105
Fix two migration issues with Maniphest

Summary: The new editor saves tasks before applying transactions, so fields need default values.
Also, I goofed the table name.

Auditors: btrahan