Improve vagrant support

EDIT: Ok, this has officially turned into a larger devX ticket, and is no longer just about vagrant-cachier support. Updated title.

## Todo

- [x] add vagrant-cachier support
- [x] move vagrant config files into subdir
- [x] separate scripts in own files
- [x] simplify scripting
- [x] implement chef provisioning (python & postgres)
- [x] upgrade to postgres 9.2
- [x] fix `make data` - https://github.com/gittip/www.gittip.com/issues/2105
- [ ] ~~daemonize honcho/gittip - see [honcho export](https://honcho.readthedocs.org/en/latest/export.html)~~ (Complex, so save for later.)