Skins page broken [patch]

Currently if you don't have any skins available the form is empty but the "Save Configuration" button still exists. If you click it you obviously get errors because the form can't validate. So I added a simple check to see if the $skinsets variable is empty, and if it is it returns a simple message, if not it goes through with the skin set form creation.

My programming skills are not good so I will not be offended if this is NOT a good way to go about solving the issue.. just thought I'd make an attempt and solving it! :)

I've also checked to make sure the form still appears and works when there are skins available and it appears to do work!