WIP 'docker share' using rsync or sshfs - only does 'pwd'

Thought I'd just try it :)

The `--share=smb` share driver flag does not work - we need to merge #245 and some docker/pkg/mflags changes (or #243 and and some more fixes)
shrug. its trivial to move most of this setup into the iso - but for my quick hack to see how it works, its very handy.