Ignoring intellij out folder
Updating to gradle 1.12 to support java 8, and to keep it up to date
The manifest file is no longer populated with the list of files to cache if the version is blank. This is because a blank version means we're disabling the app cache, and we just want to refresh the index page to pick up the new one without the manifest attribute. Having to recache all the other files just slows this process down unnecessarily.