Clarify STRICT_ALL_TABLES instructions

Summary:
  - Mention the `[mysqld]` section.
  - Should be `sql_mode`, not `sql-mode`.
  - Improve clarity of the text.
  - Slightly nicer markup.

Test Plan: {F147076}

Reviewers: csilvers, btrahan

Reviewed By: btrahan

Subscribers: epriestley, spicyj

Differential Revision: https://secure.phabricator.com/D8847
Make an old migration a little more robust

Summary: See https://github.com/facebook/phabricator/pull/507

Test Plan: This is hard to test since the migration no longer runs against HEAD, but pull 507 strongly implies this is the correct fix.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Differential Revision: https://secure.phabricator.com/D8837
Fix a HunkQuery issue where no hunks load at all

Summary:
If you create a diff with no hunks (e.g., it adds a single empty file), we never attachHunks() so we throw on getHunks().

Instead, make sure changesets get hunks attached if they expect it.

Test Plan: Created a new diff with a single empty file in it.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: zeeg, epriestley

Differential Revision: https://secure.phabricator.com/D8842
Better specificity on timeline icons

Summary: I did the math wrong here, plus better specificity just in case.

Test Plan: View comment box on timeline, verify icons are properly spaced now.

Reviewers: epriestley, btrahan

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D8848
Merge branch 'master' of github.com:facebook/phabricator