Always run a small ES instance for testing

so that people don't have to stop the regular one,
run a new one in the foreground etc.
This should be much simpler.
Remove the README steps about running a second ES

way too much trouble.
Restart main elasticsearch instance on provision
Adjust hardware settings with env vars
Suggest 'vagrant provision' to modify es memory

puppet now calculates it so we don't need to edit the file.