WallGreetingButton adds a button to Message Wall pages that allows users to easily edit their Wall Greeting. Message Wall Greetings allow you to write an arbitrary wiki-page and paste it at the top of your wall page but this feature is not exactly easily discoverable. This tool is both a convenience, and provides a means for less skilled users to access the feature.
To make a "protect" option appear, just add WallGreetingButtonProtect = true; above the import. For a ?action=raw button, add WallGreetingButtonRaw = true; above the import.
Wall greetings can only be edited by the user who owns it as well as the wiki's admins. As such, the wall greeting button will only appear on each user's own Message Wall. The only exceptions are the administrators, Discussions Moderators, Helpers, Staff and VSTF members who will see the button on every Wall.