[#255] Break Action API reference into multiple pages
[#255] Autodoc API functions in source order

Put autodoc function listings in source order (was previously
alphabetical order) in docs.
[#255] Replace ckanclient Loading Data example

Replace the example of loading data using ckanclient in the docs with
one using the action api.

The rest of the Load Datasets page of the docs still looks pretty out of date.
[#255] Add an assert to an api example in the docs
[#255] Remove API Quickstart Tutorial file

It had already been removed from the table of contents
[#255] Edit DataStore API docs intro

Remove some unnecessary explanation, just refer to the Action API docs
instead.
[#255] Tweak some DataStore API example URLs

You don't actually have to put the version number in the URL, since it
defaults to 3 and 3 is the only possible version number.
[#255] Update an example API URL

Use action api not rest api