PR comment fixes and changed 'save' button terminology
fixes recommend from pull request, 'attach' -> 'save draft', and bug in section partial
overlay on submitted free responses
YT change
Merge pull request #191 from lml/jpslav-student-work

Multiple free responses; image free responses
fixing bad migration
updated tutorials page with 2 new videos
updated readme
updates to readme
Merge pull request #195 from kjdav/newhelpvids

updated tutorials page with 2 new videos
js missing template
added response timing back into feedback
first pass at analytics
standalone bar
cleanup
finished rough draft of student analytics
feedback credit window
updated feedback notification to include info about credit window (when appropriate)
added instructor views for analytics, reused same partial
made counts of problems include partial wrong credit in analytics