Summary: this then enables people to create blog.theircompany.com. And for us, blog.phacility.com...!
Test Plan:
- created custom URIs of various goodness and verified the error messages were sensical.
- verified if "false" in configuration then custom uri stuff disappears
Reviewers: epriestley
Reviewed By: epriestley
CC: aran, Korvin
Maniphest Tasks: T1373
Differential Revision: https://secure.phabricator.com/D3542
