MDL-47453 plagiarism: Add function to verify user acceptance of EULAs

Signed-off-by: Tony Butler <tonyjbutler@gmail.com>
MDL-47453 mod_assign: Verify user acceptance of plagiarism EULAs

Signed-off-by: Tony Butler <tonyjbutler@gmail.com>
MDL-47453 mod_forum: Verify user acceptance of plagiarism EULAs

Signed-off-by: Tony Butler <tonyjbutler@gmail.com>
MDL-47453 mod_workshop: Verify user acceptance of plagiarism EULAs

Signed-off-by: Tony Butler <tonyjbutler@gmail.com>