R1:698ec68327c9

General Herald refactoring pass

Summary:
**Who can delete global rules?**: I discussed this with @jungejason. The current behavior is that the rule author or any administrator can delete a global rule, but this
isn't consistent with who can edit a rule (anyone) and doesn't really make much sense (it's an artifact of the global/personal split). I proposed that anyone can delete a
rule but we don't actually delete them, and log the deletion. However, when it came time to actually write the code for this I…