Expose Cython definitions for cimport

[michaelmior]

It would be great if pxd files were included so they could be imported by other modules using Cython.

[remiadon]

Any news on this ?

@michaelmior not sure this is doable. I already asked a similar question on roaringbitmap, an implementation entirely written in Cython, here is the thread

[Ezibenroc]

Hello, sorry for the delay. I am not super familiar with Cython, so I do not know how to do this. If you want to give it a try, pull request welcome.