Add Hosted/Remote filtering to Diffusion

Test Plan: Did searches in Diffusion using all 3 Hosted values

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley

CC: Korvin, epriestley, aran

Differential Revision: https://secure.phabricator.com/D7927
Simplify PHUIObjectBoxViews handling of Save and Error states

Summary: This removes the bulk of the "Form Errors" text, some variations likely exists. These are a bit redundant and space consuming. I'd also like to back ErrorView more into PHUIObjectBox.

Test Plan: Test out the forms, see errors without the text.

Reviewers: epriestley, btrahan

CC: Korvin, epriestley, aran, hach-que

Differential Revision: https://secure.phabricator.com/D7924
Mark answers as page objects in Ponder

Summary:
Fixes T4306. We should clear notifications about a question and its answers when viewing a question page.

(Eventually we might have an answer detail page and send the notification there, and then only clear there, but this cleans things up for now.)

Test Plan: Loaded question page, verified answers appeared as page objects.

Reviewers: chad, btrahan

Reviewed By: chad

CC: aran

Maniphest Tasks: T4306

Differential Revision: https://secure.phabricator.com/D7928
Update Conpherence Panel saved

Summary: Use the new helper methods.

Test Plan: Loaded up Conpherence Prefs, clicked save.

Reviewers: epriestley, btrahan

Reviewed By: btrahan

CC: Korvin, epriestley, aran

Differential Revision: https://secure.phabricator.com/D7929