[UPDATE] Massive rework, now support Vagrant 1.6

- Also uses retryable events where possible
- Cleaned up the modules and added better abstractions
- Added clearer error messages
- Better tie in with Vagrant events
[UPDATE] added support for suspend and resume

The host will now unmount the NFS mounts on 'suspend' and remount them on
'resume'.

Plus it will unmount them on 'package' too.