cleanup of vagrant environments

Quite a lot of changes in here.  most of them will only those using `Vagrant` for testing.
But I will call out a few changes that I made to non-vagrant things to make it easier:

1. Documentation - I moved vagrant docs to their own file and wrote a bunch of stuff.
2. Added a tag for the logging tasks to make them easier to skip.
3. Created a variable for nova default schedulers so that I can override it for small VMs.
4. Made xorp service tasks more resiliant for small/slow VMs.

Vagrant specific stuff:
1. Added an allinone environment
2. Added a vagrant playbook for initial VM provisioning including networking ( emulates the bootstrap playbook )
3. Added a post-deploy playbook for creating the linux bridge device and IP'ing it.
4. Lots of tweaks to vagrant networking etc to get internal and external networks working.
reason why this is an else vs. at top level?