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.
there's a post_deploy playbook in there that ursula calls to reconfigure the linux bridge to match the neutron config.  I did in via symlink so that we can bring it into other envs like `envs/vagrant/standard` if we want to without repeating.