remove long obsolete/unused pyzfs helper script
cmd - userland programs
The 'pyzfs' script (as opposed to the python module) has been obsolete and unused since:
commit 1af68beac368dae20a9c5d738cf6b6320cf9d63a Author: Alexander Stetsenko <firstname.lastname@example.org> Date: Wed Dec 1 02:30:25 2010 +0300 278 get rid zfs of python and pyzfs dependencies
so let's stop shipping it etc.