Summary of bug description
   * Actual behaviour: QmitkFunctionality only offers a convenient method for using a wait curson
   * Expected behaviour: Using a busy cursor would be nice, too
 
Cause of the bug
Missing method

Proposed solution
Add methods BusyCursorOn() and BusyCursorOff() which call the appropriate Qt commands to change the cursor

Affected classes
QmitkFunctionality.cpp

How will the bugfix get tested?
Manually; use the method, look if cursor changes; busy cursor is used e.g. in BasicImageProcessing