Use ApplicationSearch in Feed

Summary: Ref T2625. This doesn't do anything fancy, but gives feed a little more flexibility.

Test Plan: Viewed `/feed/`.

Reviewers: btrahan, chad

Reviewed By: chad

CC: aran

Maniphest Tasks: T2625

Differential Revision: https://secure.phabricator.com/D6681
Paste - add support for email replies and subscribers

Summary: Email replies and subscribers seem to go hand in hand so deploy both at once.

Test Plan: played around with bin/mail. Verified replies posted comments on the paste.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T3650

Differential Revision: https://secure.phabricator.com/D6682
Improve `phd` help

Summary: Fixes T3680. One description was wrong, and clean up some of the other stuff.

Test Plan: Ran `phd`.

Reviewers: btrahan, Korvin

Reviewed By: Korvin

CC: aran, jifriedman, Korvin

Maniphest Tasks: T3680

Differential Revision: https://secure.phabricator.com/D6683
Add Hovercards / restyle feed one line stories.

Summary: This adds hovercards to most stories and removes the profile photo from one line stories. I don't know about my implementation, which has difficulties with application transactions (because it shows status). Which leads me to a bigger question, which is can we render all people through a common function like AphrontTagView so we can easily class and/or hovercard it anywhere.

Test Plan: Reviewed my feed, various stories.

Reviewers: epriestley, btrahan

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D6684
Add example for bugtraq.logregex with two parts

Summary: Also fix displaying array examples.

Test Plan: Used it in `linkBugtraq()`.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T3620

Differential Revision: https://secure.phabricator.com/D6667
Merge remote-tracking branch 'upstream/master'