Versions attached to @api-see now follow through

[erunion]

This fixes an issue with @api-version usage when used on @api-see annotations, where the following would not add the supplied version to the also supplied see:

/**
 * @api-label Play representation
 * @api-field play
 * @api-type representation
 * @api-version >=3.3
 * @api-see \PlayResponse::_json play
 */

Now, with this, play is under >=3.3, as well as everything within \PlayResponse::_json.

I also added some improved assertions in a few tests, moving them away from count assertions and onto direct array key comparisons, making it loads easier to debug failures.

Fixes #30.