Updated the wiki article for the new docker hooks and descriptions.
before_bundle_exec should not be used.
after_code should be used in stead.
Adding plugins with the hook
before_bundle_exec causes build errors due to the fact that both hooks run as the
root user, but the
chown command runs after
after_code but before
This causes plugins that are git cloned in the
before_bundle_exec hook cause the build to fail (see how it happens here).
$home so it looks more like the current yml description files.