Summary:
introduce an abstract "PhameBlogSkin" class and instantiate two versions -- PhabricatorBlogSkin (Default) and PhacilityBlogSkin.
Most notable hack is including the directory /rsrc/images/phacility - this lets things "work" without messing around with the phacility.com CSS and instead just cutting and pasting most of the file.
Test Plan: played around with Phame a bunch. In particular, created a blog with a custom domain and the phacility skin. Verified it looked good and individual posts looked okay.
Reviewers: epriestley
Reviewed By: epriestley
CC: aran, Korvin
Maniphest Tasks: T1373
Differential Revision: https://secure.phabricator.com/D3687
