publish: Make publisher more powerful and better exposed on the command line. * Make the `chef publish` command have one sub-command per publish target. * Add custom argument parsing per publisher to have strong extra arguments available per publish target. * Make publish targets a first class citizen of the `PieCrust` app class.

--exclude=build
--exclude=dist
--exclude=docs/_cache
--exclude=docs/_counter
--exclude=bower_components
--exclude=node_modules
--exclude=docs/raw
--exclude=*.egg-info
--exclude=__pycache__
--exclude=__tmpfs__