Bmcuser fixes

So, I'm slightly over my head :(

But at least before, where this provider did not work, now it does.

Notably, I'm using privlevels that correspond 1:1 with the output of ipmitool.

I'm using the @property_hash instance variable, which is the method to get the real properties of instances.

The user list 1 output does now correctly parse, and `puppet resource bmcuser` actually works now.

There is still plenty of work to do. But at least now it actually does query + create users (granted, it does not converge yet. There is still work to be done on the exists? function)