switch to iframe/HTML5 player inject with IFrame Player API https://developers.google.com/youtube/player_parameters#IFrame_Player_API
and add mute audio option on autoplay if iframe/HTML5 is selected

git-svn-id: https://plugins.svn.wordpress.org/youtube-channel/trunk@868764 b8457f37-d9ea-0310-8a92-e5e31aec5664
use native WP remote file download function wp_remote_get to fetch feeds, implement converter that will port pre-2.0.0 YTC widgets to 2.0.0+ version, fix playlist parser (now allowed dash and underscore in playlist ID)

git-svn-id: https://plugins.svn.wordpress.org/youtube-channel/trunk@868765 b8457f37-d9ea-0310-8a92-e5e31aec5664
fix stable version

git-svn-id: https://plugins.svn.wordpress.org/youtube-channel/trunk@868768 b8457f37-d9ea-0310-8a92-e5e31aec5664