add choice of PXE to Vagrantfile
allow other hosts to connect to forwarded port 3000
share vagrant management network settings between providers
extract ADMIN_IP constant
make the number of controller/compute nodes configurable
the two boxes total only ~2.6GB :-D
fix networking for controller/compute
allow SLES 11 SP3 box name to be set via environment
change default SP3 box name to match new IBS boxes

Now being built here:

https://build.suse.de/package/binaries/Devel:Cloud:Shared:11-SP3:Update:Vagrant/sles-minimal-vagrant?repository=boxes
remove vagrant installation instructions

these are superfluous and it's not the right location for them anyway
standardize on VAGRANT_ prefix for environment variables
deprecate manual box building process
move provisioning scripts into provisioning/
improve PXE booting options
VirtualBox SCSI controller fix from Nanuk
drop crmsh patch which is already released