Failed logins redirect back to main page.
 - addresses issue #20
 - TODO notify the user that the login has failed
fixed typo in image path
whitespace
Refactored to remove undefined variable warnings
Moved state initialization to the beginning of the file
Updated possible range of years for course creation
Merge branch 'dev' into bug_fixes

Conflicts:
	templates/single-assignment.php
Fixed typos caused by merge