Make PhameBlogs respect policies

Summary:
Adds "can view" and "can edit" policies to blogs. Replaces "bloggers" with "can join".

This doesn't fully remove "bloggers" because I didn't want this to get too crazy/huge.

Test Plan: Created, edited, deleted blogs.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T1373

Differential Revision: https://secure.phabricator.com/D3693

resources/sql/patches/phamepolicy.sql

@@ -0,0 +1,18 @@
+ALTER TABLE `{$NAMESPACE}_phame`.`phame_blog`
+  ADD `viewPolicy` varchar(64) COLLATE utf8_bin;
+
+UPDATE `{$NAMESPACE}_phame`.`phame_blog` SET viewPolicy = 'users'
+  WHERE viewPolicy IS NULL;
+
+ALTER TABLE `{$NAMESPACE}_phame`.`phame_blog`
+  ADD `editPolicy` varchar(64) COLLATE utf8_bin;
+
+UPDATE `{$NAMESPACE}_phame`.`phame_blog` SET editPolicy = 'users'
+  WHERE editPolicy IS NULL;
+
+ALTER TABLE `{$NAMESPACE}_phame`.`phame_blog`
+  ADD `joinPolicy` varchar(64) COLLATE utf8_bin;
+
+UPDATE `{$NAMESPACE}_phame`.`phame_blog` SET joinPolicy = 'users'
+  WHERE joinPolicy IS NULL;
+