wip: Initial creation of class_dashboard django app
wip: adding files from sandbox
wip: deleting models because we don't need them
wip: Added code that retrieves the needed data for attempts and opens
cherry-pick of cherry-pick 98708bfde8^..0b571c19eb
wip: small fix with calculating text length
wip: attempts visualization on front end
wip: Did use proper convention with the tag variable.
wip: Add visualization of how many students opened each subsection
wip: Add grade distrubion per section visualization and remove top graph of all problems
wip: Oops, didn't include the needed javascript file
Typo in value displayed for attempts
wip: small tweaks
wip: add some nicer css
wip: rename Class Dashboard to Metrics in front end
wip: missed a file in the rename to metrics
wip: fix tooltip not appearing at the right spot
wip: New layout and javascript code to make all three graphs in one file
wip: Update default colors, make tooltip move to left of cursor when too far right
wip: New colors