Fix bug with `arc unit --everything` when coverage is available

Summary: We don't set $paths when running --everything.

Test Plan: Ran `arc unit --everything` with coverage.

Reviewers: vrana

Reviewed By: vrana

CC: aran

Differential Revision: https://secure.phabricator.com/D5260
Add willRunTestCases / didRunTestCases hooks

Summary: These hooks allow test cases to build shared resources -- notably, database fixtures.

Test Plan: See next diff.

Reviewers: vrana

Reviewed By: vrana

CC: aran

Differential Revision: https://secure.phabricator.com/D5258
Document parameters

Summary: unlike the hooks I copy/pasted, these hooks have parameters

Test Plan: read it

Reviewers: vrana

Reviewed By: vrana

CC: aran

Differential Revision: https://secure.phabricator.com/D5264
Fix "arc" when `arcanist/` lives in some directory with spaces in the name

Summary: This shell script needs more quotes.

Test Plan: Ran "arc" with `arcanist/` inside a directory called `s p a c e s`.

Reviewers: irinav, vrana

Reviewed By: vrana

CC: aran

Differential Revision: https://secure.phabricator.com/D5265
If a revision depends on another revision which has not yet been closed, warn the developer

Summary: Have arc land inspect the revision if it depends on some other revisions which haven't been closed yet. If yes, then warn users.

Test Plan: Will test them locally.

Reviewers: epriestley, AnhNhan

CC: aran, Korvin, AnhNhan

Differential Revision: https://secure.phabricator.com/D5262
Ignore remote errors in parsing Mercurial log

Summary:
This probably indicates some none fatal error, e.g.:

> remote: Certificate invalid: name is not a listed principal

The best thing here would be to avoid the error but we shouldn't explode even if it is there.
I tried to mute the error from the output but didn't find a switch or config option to do it.

Test Plan:
  $ hg outgoing --branch default --style default

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D5267
Minor, fix `arc land` for the case of no dependencies.

Auditors: Afaque_Hussain
Improve the description of using `arc land --revision`

Summary: The message suggests that only one revision would land.

Test Plan: Read it.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D5277
Initialize variable in lint patch output
Dispatch an event in arc land right before pushing a revision

Summary: I looked at the pros & cons at adding hooks in git/hg vs arc land and I prefer arc land.

Test Plan:
* added an event listener and made sure I could handle the event.
* made sure things get reverted when the event handler throws an exception.

Reviewers: vrana, epriestley, pieter

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D5268
Improve Windows compatibility

Test Plan:
  $ arc liberate
  $ arc lint

Reviewers: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D5319
Compute lint cache key before linting

Summary: If user changes the file contents during linting (usually when prompted to apply a patch) then we save the old messages to the new file contents. Fix that by computing the hash before linting (or after applying patch).

Test Plan: Changed the file during linting, verified that the file hash didn't change.

Reviewers: epriestley

Reviewed By: epriestley

CC: ptarjan, aran, Korvin

Differential Revision: https://secure.phabricator.com/D5320
Change arc feature to use it's own config key for the start default

Summary:
Changes arc feature to read 'arc.feature.start.default' instead
of 'arc.land.onto.default'.  In our usage we actually need to fork off
a different branch than we land to, so separating these is useful.

Test Plan:
Set arc.land.onto.default = master
Set arc.feature.start.default = bar
arc feature foo
cat .git/config
Verified the foo branch tracked bar

Reviewers: epriestley, nh

Reviewed By: epriestley

CC: wez, dschleimer, aran, Korvin

Differential Revision: https://secure.phabricator.com/D5336
Parsing rcsdiff -u

Summary: Added some sample rcsdiffs for adding and deleting a line from a file. Wrote some test cases to be tested by ArcanistDiffParser.

Test Plan: By making all the test cases pass.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin, AnhNhan

Differential Revision: https://secure.phabricator.com/D5324
Don't use absolute path in `ArcanistDiffUtils`

Summary: Improves Windows compatibility.

Test Plan: Ran failing unit test on Windows.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D5344
Merge remote-tracking branch 'upstream/master'