-- Changed docstrings to use double quote.
-- More consistent naming for youtube IDs (normal_speed_id -> youtube_id_1_0).
-- Formatting changes for readability.
-- Updated test XML to expect JSON-encoded strings; prevents tests from spuriously failing.
* New format: {tag}://{org}/{course}/{category}/{name}[@{revision}]
* Updated tests, code
* Added test chapter with : in url_name in toy course
* added test html page with : in url_name
* added a note to docs
* course roots live in roots/{url_name}.xml
- one is linked from course.xml
* policies live in policies/url_name.json
- loaded based on course url_name
* Updated to pass policy through into xml parsing, so it takes effect
before descriptor constructors are called.
* Update toy test course to new structure, fix up tests
