Don't use beanstalk client directly, subclass custodian/queue, or similar
to allow us to swap out the queue and stub it for testing.

The alerter needs to be overhauled since it relies upon the old hash-based approach.

make Custodian::Parser::Macro a class.
Use that, and make sure that we return such a thing when we define a new one.

Look at certificate validation with curb.

Update README to be polite, accurate, and make no mention of JSON.