changes box from ubuntu/bionic64 to hashicorp/bionic64 as Canonical doesn't have a vmware box
makes it obvious how to allow the VM to show up in the hypervisor GUI
updates vmware provider to be the official vmware_desktop provider
Adds a VM display name option
Changes gpg key imports and rvm install to match what's in omnibus
handles stderr better to avoid some extra warnings unless there's a real failure
Installs Ruby only if it's not installed already (nicer if have to reprovision the box)
switches back to gem install bundler due to upstream bundler/ruby changes
adds --quiet to gem install bundler to avoid progress bar junk