remove use of ngettext in discussion jasmine test
Merge pull request #5051 from edx/jsa/fix-thing

remove use of ngettext in discussion jasmine test
Add commands.
Work in progress.
Add fixes.
Fix keyboard navigation.
Add small fixes.
Fix styles.
Add fixes.
Add fixes.
Fixed typo and indentation.
Added positioning. Moved context menu code into its own module.
Collision detection works for menu. Sub-menu still has to be done.
Add i18n and small fixes.
Collision detection works for sub-menus.
Cleaned up collision detection code.
Addressed comments.
Limit boundaries of context menu to video element not enclosing div.
Small reactoring.
Fixed tiny alignment problem with sub-menu.