Separate creating the mudlet instance from accessing it.

In situations where something tries to access mudlet (the class), after it
is destructed, make it easier to tell what is going on.
Yes, mudlet:: is an error here. I don't know why I wrote it like that since I originally wrote this code multiple years ago. Also, I'm avoiding making formatting changes with these patches, since they are intended to be part of a point release rather than going directly to development.