Added basic create and edit post tests.
Added header tests to create and new posts.
Added test for returning a single post.
Added response test for edit context of edit_post endpoint.
Added format, password, date and modified date tests to check_get_post_response.
Created api comparison doc with initial pass of auth, users, and posts comparison info.
Reformat to column comparison
Correct link format
Delete meta is available on dotcom

Props @justinshreve for clarifying.
Group meta comparison
Add taxonomies comparison
Add media comparison
Add comments comparison
Add further site comparison docs
Add XML-RPC comparison
Add key
Add post periphery comparison
Add revision comparison
Add custom authentication comparison
Add page comparison