Form Min-Max size and Fixed-size

[Victor Bravo VI]

As another note, that SubclassFormMinMaxSize procedure makes rather unique use of the ComCtl32's subclassing ability to store a bit of extra data. Each subclassing can store 4 bytes. I needed 8, so I created a second "dummy" subclassing for the extra 4 bytes.

Actually, the uIdSubclass parameter can also be used to store the other 4 bytes, so the 2nd subclass is unnecessary.