Re: Nim for Windows: MinGW vs TDM-GCC

[mratsim]

@oyster:

I may have misconfigured the unit tests import in arraymancer. I use Appveyor 
for testing on windows with mingw-w64, and OpenBLAS is imported and loaded 
correctly: See 
[here](https://ci.appveyor.com/project/mratsim/arraymancer/build/56).