Add Windows build support

[diego-plan9]

Description and motivation

Currently, the build system has not been checked and adjusted in order to support Windows-based systems. While in theory cmake should help us in the process, it has not been tested and it is likely lacking some Windows-specific adjustments. We should revise the build system in order to allow easy compilation on Windows machines as well, as well as updating the documentation accordingly if needed.

Proposed solution

Alternatives and other information

Travis Windows support can help in automating and verifying the changes.

[diego-plan9]

Thanks to the great effort from @filemaster in #58, as of a158e27 it should be possible to compile the library in Windows: an overview and some pointers have been added to the documentation as well.

Please note we marked the support as experimental as there are still some rough edges and tweaks to be made (in particular, building with CUDA support might require additional tweaks): do not hesitate on reporting and commenting while the remaining issues are tackled.

[diego-plan9]

And again thanks to #67, it should be now possible to build the CUDA-enabled version of the library.

[Borjagodoy]

We have support to window using WSL! We therefore proceed to close this issue and add it to the documentation.