renamed foo_handler to save_handler
normalize youtube short links; fixes #40
accept youtube video IDs containing - characters; fixes #46
show video window in author mode
Merge branch 'master' of https://github.com/virtUOS/mooc.ip

Conflicts:
	blocks/VideoBlock/VideoBlock.php
Merge branch 'master' of https://github.com/virtUOS/mooc.ip
replacing matterhorn 'watch' links by 'embed' links; fixes #41