Remove "Python" suffix from Python modules
Each python module was needlessly split into two parts: vtkCommonCore.py called "from vtkCommonCorePython import *" to make itself into a copy of vtkCommonCorePython.so.
If the "Python" suffix is removed, then "vtkCommonCore.so" can be imported directly. This simplification also seems to help PyCharm perform its introspection of the modules.