Be forceful when removing on debian
Be forceful when removing on debian

deluser and delgroup commands will fail if processes are still
owned by the user.  This commit does a
`pkill -u {{package_install_user}}` to kill any lingering
processes before attempting to delete the user.

Addresses: #9

dergraf/node_package,xorver/node_package,yoonka/node_package,basho/node_package,xorver/node_package,dergraf/node_package,yoonka/node_package