disable python3 bindings for the moment In a second time, this patch might be removed to take advantage of the newer python3 bindings coming with kmc 3, but let's disable them for the moment.
support mixed machine capabilities without impeding the build This allows one to build the package with almost any combination of machine capabilities. The initial issue was reported against -march=x64-64-v2, but the present patch extends to v3, and probably any combination thrown by a -march=native. The issue seems tied to the way the build process is modified by debian, so may not be very relevant cherry picked upstream. . Diagnostics information is kept around just in case, for convenience.
