Change the folder hierarchy.

This allows the user to "vagrant ssh" from any of the app repositories,
rather than having to chdir to metacpan-developer first.  Also, adds a
script to do the cloning.
Adds note about dealing with folder mounts and guest additions.
Use carton to install modules in provisioning.
Adds script to get a partial mirror of CPAN.
No need to chown app folders anymore.
Cut down on number of modules we need to install outside of Carton.
Enable pre-commit hooks in init script.
Run carton as part of provisioning, but don't use sudo.
Merge branch 'master' into move-folders

* master:
  Suggest 'vagrant provision' to modify es memory
  Adjust hardware settings with env vars
  Restart main elasticsearch instance on provision
  Remove the README steps about running a second ES
  Always run a small ES instance for testing
  Specify a few more missing modules

Conflicts:
	provision/after/perl_mods.sh