Update to 1.2 from WordPress.org SVN trunk
capital_P_dangit
Making a lot of improvements for integration on WordPress VIP

* Add phpDoc
* Bump version on enqueued script
* Add escaping for output
* Factor out duplicated logic for constructing embed code
* Add third argument to shortcode_atts
* Apply WordPress Coding Standards
Refactor plugin functions into class methods
Merge pull request #2 from x-team/master

Various improvements to plugin in course of integration on WordPress VIP