Post points hook: Don't delete posts for auto-drafts

We were running the delete portion of the hook for auto-draft posts,
which was removing points. This wasn’t intended.
Don't award or remove points for non-public points types
Uninstall: avoid a fatal error in the points component by including dependencies

Fixes #16
Periodic points hook: hook into 'init' instead of 'set_current_user'
Update change log for 1.1.2
Tag version 1.1.2