CLIMATE-437 - Remove provision-er from Vagrantfile

- The VM init script requires some user input and the default Vagrant
  provisioner doesn't seem to allow for that. Until a better solution is
  found, the initialization script needs to be called manually after
  creating the new VM. Check the documentation on the OCW wiki at [1]
  for additional info.

[1] http://s.apache.org/Rxd