Update Railo 4.2 to the release version

Closes #11
Update webroot path for Railo 4.2+

It seems Railo have moved the webroot from "www" to "ROOT" in the
Railo 4.2 release. An updated helper script is required to handle,
easiest way was just to copy the old railo helper and update.
Merge pull request #12 from marcins/feature/railo-42-release

Add Railo 4.2 release support