Update spelling data

Summary: Update `ArcanistSpellingDefaultData` with data from the [[http://anonscm.debian.org/gitweb/?p=lintian/lintian.git;a=blob_plain;f=data/spelling/corrections;hb=4b3fc40babff01874b54718406b77b7f3052d26a | original source]].

Test Plan: Visual inspection.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9790
Enable unit tests for `ArcanistJscsLinterTestCase`

Summary:
https://github.com/mdevils/node-jscs/issues/444 has been resolved in commit [[https://github.com/mdevils/node-jscs/commit/0de667bac2491ba04d930ff94e990965213ba36b | 0de667bac2491ba04d930ff94e990965213ba36b]], which means that `jscs` can be easily run on files with any extension.

NOTE: JSCS version 1.5.7 is required.

Test Plan: `arc unit`

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9789
Refactor author handling in the Mercurial API

Summary: There were two callsites which needed some information from the username. Only one worked "correctly", causing `arc diff` to not amend commits anymore because the author could not be parser.

Test Plan: run `arc diff` with changes

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9797
Alphabetize `.arclint` linters

Summary: I'm a bit OCD with this, but I find the `.arclint` file easier to read if the keys are in alphabetical order.

Test Plan: N/A

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9804
Merge branch 'master' of github.com:facebook/arcanist