Avoid MR in askari provision, we don't need it.

This helps trim some memory footprint.  Other small tweaks as well.
Switch to binstubs by moving existing `bin/` -> `exe/`.

Aside from the (no longer) overloaded nature of `bin`, there appears
to be no downside.  Why didn't we do this before?
Merge pull request #116 from seomoz/phs/vagrant-provision-tweaks

Phs/vagrant provision tweaks