Makes knowledgemap work with most recent routers.
Merge branch 'develop' into knowledgemap
Fixes some race conditions in knowledgemap rendering. Allow all nodes to be displayed.
Merge branch 'develop' into knowledgemap
Merge branch 'develop' into knowledgemap

Conflicts:
	kalite/distributed/static/js/distributed/topics/router.js
Refactors router.
Properly checks if we are at the Exercise level.
Ensures khan import stamps paths on exercise and video data.
Prevents modal popup for exercises interfering with knowledgemap overlay styling.
Fixes exercise rendering.
Allows views to navigate by adding slugs rather than absolute paths.
Properly sets path attribute on videos and exercises for khan content.
Updates khan content metadata.
Fixes linting.
Merge pull request #2662 from rtibbles/knowledgemap

Makes Knowledgemap function