API proposal - first commit
added more api details, including answers to @cdeil's questions
a little more organization for the doc
added "base class" for astroquery api
added Delayed class
fixed code block formatting errors
moved api.rst
added example to api.rst
api update
Merge branch 'api_proposal' of github.com:keflavich/astroquery into api_proposal

Conflicts:
	docs/astroquery/api.rst