By definition, the way to determine from the version string if a release is a GA release or a pre-release is to check if the PRE string is empty. If it is empty, it's a GA release, otherwise it's not.

While this is logical from a theoretical point of view, it is not immediately obvious to developers.

We should create a variable VERSION_IS_GA that will evauate to "true" if PRE is empty, and "false" otherwise.