filter stats by class
Merge branch 'master' into reports-improvements-3333
fix jslint
Merge remote-tracking branch 'origin/campus-3154' into reports-improvements-3333
fix classes filter layout
Merge branch 'master' into reports-improvements-3333
fix forum class filters
fix classes filters
Merge branch 'master' into course-header-3646

Conflicts:
	themes/default/templates/administration/stats.html
refactor template tag name and check if user is admin
fix zero division and no attribute erros
make reports and messages work inside and outside course admin
show incons in course intro
change classes link position