[backbone/grading] fix
Fix sample/students
Put notes and contacts under tabs in student show
[grading] live calculation completion percentage graded/ungraded/total
fix and add exam completion info in course exams table
Create students edit
Refactor guardians list under students
Merge remote-tracking branch 'kalkov/refactor_students' into develop
refactor dublication exam instance methods
Merge branch 'develop' of https://github.com/absolu7/GAKUEngine into develop
Fix admin creation when app is installed
Merge remote-tracking branch 'tapalilov/develop' into develop
Merge remote-tracking branch 'kalkov/develop' into develop