Add message to indicate the user check was completed

Code looks good. We'll get this tested soon.

Before this patch I saw no messages upon success or failure (on failure though it did populate the table in the bottom with the users that failed under the title of "Found 1 user whose email address is not valid.")

Upon adding this patch to the module for a success I received a green message at the top of the form of "Look for the verification results below the form."

The same message occurred when an email was not validated. Except when a users email did not pass validation the table shows the user id that failed and gives the reason why it did. Instead of no users being listed in the table and a message of "All email address checked passed the verification(s)." which is what occurs when all checked users email passed validation.

This has passed testing.

Thanks!