Summary: Explain what lint is, how to configure it, what we ship with, etc. Also wax philosophical.
Test Plan: Generated docs, read "carefully".
Reviewers: csilvers, btrahan, vrana
Reviewed By: vrana
CC: aran
Differential Revision: https://secure.phabricator.com/D2628
Summary: As per discussion with @johnduhart, improve documentation around
reusing and customizing linters.
Test Plan: Generated and read documentation.
Reviewers: btrahan, jungejason, johnduhart
Reviewed By: btrahan
CC: aran, epriestley
Maniphest Tasks: T795
Differential Revision: https://secure.phabricator.com/D1501
