Docs audit - plugin.php.
Allows adding of post id through post vars to allow image to be associated with post
Convert empty attachment sizes to empty object intead of array

WP-API issue #299
Remove references to removed $fields parameter

The `get_post()` and `prepare_post()` methods apparently had a
`$fields` parameter at one time. This has been replaced by the
`$context` parameter.

When the `$fields` parameter was removed, some of the inline docs
stayed behind. This removes them.
Add summary of the $context parameter

For the `get_post(s)` methods, I think only the `’view’` context is
used internally, but I’ve referenced `’edit’` there as well.
Corrected cookie authentication docs example to match changes in js-client.
User's ID should alway be integer

When user that doesn't have `list_users` capability request its own data using `/users/me`, they are redirected to `/users/<ID>`, which means ID is passed as a string to `WP_JSON_Users::get_user()`. As `get_current_user_id()` returns integer, and there is strict comparison, this will fail.

User's ID should be converted to integer, or there shouldn't be strict comparison.
Merge pull request #321 from WP-API/cookie-docs-fix

json_register_scripts - wpApiOptions.nonce is now WP_API_Settings.nonce
Merge pull request #333 from dimadin/patch-1

User's ID should alway be integer.  Closes #333.
Merge pull request #326 from JDGrimes/fields-parameter-docs

Remove references to removed $fields parameter
Permissions to upload by post id changed

- Now checks the post type of the post id being passed
- Rename variable to make it clearer we are trying to upload to it (post_parent)
Merge remote-tracking branch 'upstream/master' into media-upload-to-post
Conflict.
More inline documentation improvements for plugin.php.
Some globals definitions.
Merge pull request #293 from DrewAPicture/standards

Docs audit - plugin.php.
Merge pull request #300 from maxcutler/issue-299

Convert empty attachment sizes to empty object intead of array
Merge pull request #294 from pkevan/media-upload-to-post

Allow attaching media to posts on creation