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Adds an option to allow sending unified diff contexts in differential mails.
Make comments easier to read.
Adapt to style changes; fix performance bug when loading hunks for changesets.
Minor, fix 404 page.
Merge pull request #180 from r4nt/differential-unified-comments

Adds an option to allow sending unified diff contexts in differential mails
Support symbol linking in Remarkup code blocks

Summary:
Trigger the crossreference behavior on code blocks. Limited to
Differential, where we know what the project is, but includes regular
comments, inline comments, and previews of both.

(Hopefully event handlers on deleted elements also get deleted, so we
don't leak memory? Also, caching is a problem, and I didn't find a way
to mark existing cache entries as stale, like
`DifferentialChangesetParser::CACHE_VERSION`...)

Test Plan:
Load Differential revision, make lots of comments, click on
things.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T1602

Differential Revision: https://secure.phabricator.com/D3283
Add a sprite generation script to Phabricator

Summary: This probably needs some tweaks, but gets the point across. I'll lay in the actual usage in the next diff.

Test Plan: Looked at generated CSS/PNG.

Reviewers: btrahan, chad, vrana

Reviewed By: vrana

CC: aran

Maniphest Tasks: T1569

Differential Revision: https://secure.phabricator.com/D3278
Use sprites for all the menu icons

Summary:
See D3277, D3278.

  - Sprite all the menu icons.
  - Delete the unsprited versions.
  - Notification bolt now uses the same style as everything else.

Test Plan: Looked at page, hovered, clicked things.

Reviewers: btrahan, chad, vrana

Reviewed By: vrana

CC: aran

Maniphest Tasks: T1569

Differential Revision: https://secure.phabricator.com/D3279
Use sprites for (nearly) all application icons

Summary: Sprites for everyone.

Test Plan: Loaded `/applications/`.

Reviewers: btrahan, chad, vrana

Reviewed By: vrana

CC: aran

Maniphest Tasks: T1569

Differential Revision: https://secure.phabricator.com/D3280
Optimize matching regexps in Herald rules

Summary:
We spend 6.37 s in this condition on a big diff.
By adding the 'S' flag, the time is down to 2.15 s.

Test Plan: `DifferentialRevisionEditor::newRevisionFromConduitWithDiff()`

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D3284
Switch metamta.differential.unified-comment-context to false by default, this is a little intense for non-mailing-list-installs.
Minor, fix a variable issue with new context commenting.
Show list of non-exited daemons

Summary: This is arguably a more useful view than listing all daemons.

Test Plan: Looked at list, only saw daemons that haven't exited

Reviewers: vrana, epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D3286
Register commits as Diffusion fact objects

Summary:
We will need to process them.
Maybe it will fit better in Repository application but we don't have it yet.

Test Plan:
  $ ./fact cursors

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin, royw

Differential Revision: https://secure.phabricator.com/D3287
Allow installs to configure an arbitrary block of HTML to show on the login screen

Summary: For secure.phabricator.com, I've wanted to put up a "you can use demo/demo" message for a while. Wikimedia also wants to add some custom login instructions.

Test Plan:
Configured this:

    'auth.login-message' =>
      '<div style="width: 50%; margin: 1em auto; padding: 1em; border: 1px solid green; background: #dfffdf;">'.
        '<strong>Welcome!</strong> Lorem ipsum...'.
      '</div>',

...got this:

{F17167}

Reviewers: btrahan, vrana

Reviewed By: btrahan

CC: aran, jeremyb

Maniphest Tasks: T1637

Differential Revision: https://secure.phabricator.com/D3288
Expose xhpast via Conduit

Summary:
Create `phpast.{version,getast}` methods for calling xhpast
with `--version` and with source code as input, respectively.

Test Plan:
Run `arc call-conduit` a bunch of times; delete xhpast; run
it a bunch more times.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T1534

Differential Revision: https://secure.phabricator.com/D3289
Make countdowns (internally) embeddable

Summary:
You can now embed countdowns in Remarkup! Not sure what it's
useful for, but there you have it.

Also I may have made a hash of the markup code; I don't really know what
I'm doing.

Test Plan: Make a new countdown, put `{C###}` in a Differential comment.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T1053

Differential Revision: https://secure.phabricator.com/D3290
Fix a f()[0] use in rPd45855e33e0b98d521ea3e44a4c1f718821ec6cc

Summary: See D3291.

Test Plan: Ran `phpast.getast` via API.

Reviewers: alanh

Reviewed By: alanh

CC: aran

Differential Revision: https://secure.phabricator.com/D3292