Zen documentation need some love

Usually, documentation for themes is merged among versions which is confusing and makes it hard for starters to dive in.

It is a task to hunt information only for specific version and there are many pages related to legacy modules or procedures that are not relevant anymore so they may be confusing to those trying to get the needed information to build on last and latest version.

I suggest that there should be different branch in documentation on Drupal.org devoted to 6.x branch as many things are completely different so maybe splitting to 6.x-1.x and 6.x-2.x (for legacy), 7.x-3.x, 7.x-5.x and 7.x-6.x (with future 8.x) would make sense and would help people tracking what they need without burden, figuring out that something is related to some other version.

Also documentation needs improvement as some benefits that are presented as common for all versions are not relevant so much for the newer versions and some that are very important are not covered.

I'm willing to volunteer to make this separation.