some work here
vk authorization prepared for use
desktop.py auth_vk() now returns full user object (not just identity)
"its me" function added for instructors
Merge remote-tracking branch 'origin/vk_auth'

Conflicts:
	desktop.py
	views/desktop/templates/index.tpl
add mistakes
add mistake index of all
fixed ensure data
Merge branch 'report_mistakes' of https://github.com/proAlexandr/StudyTime

Conflicts:
	model.py
	views/desktop/static/js/app.js
	views/desktop/static/js/controllers.js
	views/desktop/static/partials/group/files.html
	views/desktop/static/partials/group/schedule/schedule.html
	views/desktop/templates/index.tpl