Shows class-hours by category on the dashboard
Adds "Grades" section on the dashboard, which shows students per grade
and number of subjects/sections available to each grade.

It still should probably be optimized better, and students per grade
currently doesn't work for programs before the current year.
Shows additional info in dashboard status popup
Changes getGrade(program) to return the grade the student was in when that program ran
Moves some logic out of getGrade() into other methods
Fixes sections attribute in class_admin_info()
Fixes query for grade_sections
Removes obsolete comment
Removes _grade property because it's unnecessary
Fix SCRMI admin panel slowness

The SCRMI detail view in the admin panel was very slow to load. This
was because it was rendering a dropdown containing all the program
modules in the database, which issues a separate query for each
program module's __str__ method.

Fix this by making SCRMI.module non-editable, so that the dropdown
isn't rendered, since we aren't going to be editing that from the
admin panel anyway.
Merge pull request #892 from learning-unlimited/mgersh-dashboard

More data on the dashboard: #733, #842, #854
Add shell_utils import to useful_scripts importer
Merge pull request #912 from learning-unlimited/scrmi-admin

Fix SCRMI admin panel slowness
Merge pull request #913 from btidor/useful_plus

Add shell_utils import to useful_scripts importer