add a /jump_to_id/ shortcut for producing more durable links between courseware in Studio
add comment and fix mistake in test
Studio: revises HTML and styling around new unit ID on unit view
add a reference in the toy course to the test jump_to_id HTML module
added explicit unit test to verify the link rewriting
add input/output information in doc strings
address review feedback
fix fat finger string formatting
add line break between arguments
add some chinese characters to the test content