Better APP_URL

Include server name.

Signed-off-by: Seth Battis <SethBattis@stmarksschool.org>
Merge branch 'refs/heads/dev-support' into dev-grading-analytics
Argh

Right. Our WWW server doesn't support PHP, so I need to come up with a better JavaScript solution.

Later.

For now: hard coding URLs!

Signed-off-by: Seth Battis <SethBattis@stmarksschool.org>