make bi open vm configurable

make bi vm configurable, bring required directory structure closer to conformance with how our other vagrant vms operate, fix service start/stop, merge 4_7_x
According to the README.md at https://github.com/xtuple/xtuple-vagrant the recommended structure is

- dev
  - xtuple
  - xtuple-extensions
- vagrant
  - xtuple-vagrant

Thus reaching `dev` from the `bi-dev-open` directory requires going up 3 levels. If you have a different hierarchy, override `xtSourceDir` in `xtlocal.rb`.