Modernized People Ldap Controller a tiny little bit

Summary: somewhat. de-uglified panels, add dust, etc. you get it.

Test Plan:
Visited, looked at nice new form.
Visited `http://phab.van/people/ldap/?import=true&usernames[]=anh&usernames[]=han&email[anh]=anh%40nhan.com&email[han]=han%40nhan.com&name[anh]=Nhan&name[han]=Nguyen` to hack in a few users. Did not work (CSRF ¬.¬), but saw what I wanted. Beautiful `PhabricatorObjectItemView`s. With color bars
These images where before the diff update. Error messages would appear as attributes (good for you that I did not include them, since it looks horrible)

The looks of it (refuse to take THIS in mobile):
{F36428}
{F36429}

Reviewers: epriestley, chad, btrahan

Reviewed By: btrahan

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D5387