#464 test Python interpreter version at module import

[Oliver Schmitz]

while using a wrong Python version users might end up with something like

Traceback (most recent call last):
  File "C:\Users\Gebruiker\Documents\6e Jaar\Python course\dynmod\snowmelt\dynMod.py", line 1, in <module>
    from pcraster import *
  File "C:\Program Files\PCRaster\Python\pcraster.py", line 5, in <module>
    from PCRaster.operations import *
  File "C:\Program Files\PCRaster\Python\PCRaster\__init__.py", line 1, in <module>
    from operations import *
  File "C:\Program Files\PCRaster\Python\PCRaster\operations.py", line 3, in <module>
    import PCRaster._PCRaster as _PCRaster
ImportError: DLL load failed: Kan opgegeven module niet vinden.

while path settings as given in the docs are fine. We could check the used Python interpreter version and raise a more informative/userfriendly ImportError message to aid users in solving the issue