Conduit APIs to start and stop tracking time in phrequent

Summary:
This adds methods to start and stop tracking any arbitrary PHID in phrequent. Currently, this uses copy-pasted code from PhrequentTrackController. I had to do this because the code to start/stop was not abstracted into a common class.

Once the code to start/stop working is extracted into a re-usable class, the conduit API can use this as well.

Test Plan: I called the functions with a PHID of a task and ensured that the fields in the phrequent database table was being updated correctly.

Reviewers: skyronic, #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: maxhodak, erik.fercak, aran, epriestley, Korvin

Maniphest Tasks: T3569, T3970

Differential Revision: https://secure.phabricator.com/D7326
Allow board columns to be reordered

Summary: Fixes T4567. This isn't going to win design awards and we have some leaky CSS, but it works fine.

Test Plan: {F176743}

Reviewers: btrahan, chad

Reviewed By: chad

Subscribers: epriestley

Maniphest Tasks: T4567

Differential Revision: https://secure.phabricator.com/D9905
Fix PhabricatorProjectCustomFields to use storage correctly.

Summary: Prevents infinite recursion when trying to save custom fields on projects.

Test Plan: Add a custom field (that is a class, not one configured in the UI) to a project, and try to save it.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Projects: #phabricator

Maniphest Tasks: T5606

Differential Revision: https://secure.phabricator.com/D9908
Show a better message for empty repositories and invalid branches

Summary:
Ref T1493.

  - When viewing an invalid branch, show a "there is no such branch" message.
  - When viewing an empty repository, show a "this repository is empty" message.

Test Plan:
  - Viewed empty, bad branch, and nonempty in Git.
  - Viewed empty, bad branch, and nonempty in Mercurial.
  - Viewed empty and nonempty in Subversion.

Reviewers: btrahan, chad

Reviewed By: chad

Subscribers: epriestley

Maniphest Tasks: T1493

Differential Revision: https://secure.phabricator.com/D9912
Fix various spelling mistakes

Summary: Minor change, self-explanatory.

Test Plan: Eye-ball it

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9911
Remove uniqueness constraint from "sequence" key in project column table

Summary: Fixes T5611. We don't need sequences to be unique, and it makes it a pain to update them.

Test Plan: Dragged some columns around.

Reviewers: chad

Reviewed By: chad

Subscribers: epriestley

Maniphest Tasks: T5611

Differential Revision: https://secure.phabricator.com/D9914
Remove user-independent date and time functions from Phabricator

Summary: These have been moved into libphutil.

Test Plan: Browsed Phabricator, didn't see a crash.

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9907
Fix issue in Mercurial repos with duplicate branch heads

Summary:
Fixes T5613. A branch may have multiple heads in Mercurial, but `executeOne()` expects exactly one result.

Load them all instead. Equivalently, we could `limit(1)`, but it's likely that we'll use the cursors in the future to reduce the number of VCS operations we do, so this is probably a little more along the lines where we're headed.

Test Plan: Poked around some repos.

Reviewers: chad, richardvanvelzen

Reviewed By: richardvanvelzen

Subscribers: epriestley

Maniphest Tasks: T5613

Differential Revision: https://secure.phabricator.com/D9918
Update Phortune UI elements

Summary:
Ref T2787. Update some of the UI elements used by Phortune. Mostly gets rid of the old blue headers.

Also adds some sweet art.

Test Plan: Poked aroudn Phortune.

Reviewers: btrahan, chad

Reviewed By: chad

Subscribers: epriestley

Maniphest Tasks: T2787

Differential Revision: https://secure.phabricator.com/D9915
Update Stripe PHP API

Summary: Ref T2787. This brings us up to date.

Test Plan: `git clone`

Reviewers: btrahan, chad

Reviewed By: chad

Subscribers: epriestley

Maniphest Tasks: T2787

Differential Revision: https://secure.phabricator.com/D9916
Add 4 more project icons

Summary: Adds 4 more icons.

Test Plan: Tested editing a project

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9919
Use `phutil_var_export` in `CelerityManagementMapWorkflow`

Summary: `phutil_var_export` produces more readable output than `var_export`. Depends on D9923.

Test Plan: Eye-balled the Celerity map.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9926
Merge branch 'upstream/master'