Changed Stable Tag For Readme

Experimenting with GitHub still
Contact Info - Validation Change

The contact information now is apart of the same validation system as
the other questions. i.e. mlwRequiredText classes.
Disable Enter Key On Quiz

Disabling enter key on quiz to prevent accidental submits.
Update Version Number And Ads Function

Bumped version number to 3.3.3 and added new ad about our add-on pack.
Updated Changelog Information

Updated changelog in readme and credits files.
Merge pull request #1 from fpcorso/Version_3.3.3

Version 3.3.3