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