Added getUserCodeClass to UserCodeWrapper

This pull request adds getUserCodeClass () to UserCodeWrapper to allow for quick access to the class.

Sopremo and Meteor make heavy use of reflection and often require access to the class of the user code.
Currently, the UserCodeWrapper only allows to return instances of the user code, not the class.
It would be possible to just call getClass() on the user code object, however this leads to unnecessary instantiations of the user code if it is provided as a class, not as object.