Python 3.7 and numpy

[cbsteh]

PySawit uses numpy, and numpy appears to be incompatible with Python 3.7. In some cases, you might get the exception ImportError thrown, with the following message:

ImportError: DLL load failed: The specified module could not be found.

This problem does not happen prior to Python 3.7. So to fix this issue, do not upgrade to Python 3.7 or later until this issue is resolved by the powers that be. I have tested on Python 3.6.6 and this problem does not occur.