Version 1.01

Fixed the following issues raising during the code review:
#1 Missing permission/login checks in web services
#2 Consider using a string to store date formats
#3 Sort type needs better validation/cleaning
#4 Hard-coded "student" role access
#5 Avoid magic numbers and use Moodle constants
#6 Functions in lib.php violate naming rules
#7 Custom actions should check sesskey
#8 Uninstall/drop tables not needed
#9 install.xml looks hand-rolled