[Dev] setPinned design problem

[John Anderson]

I'm hoping that setPinned goes away, but if it doesn't it has the 
familiar problem that if two different people, who don't know about each 
other, try to pin and unpin the object pinned state it gets out of sync. 
The usual solution for this problem is to have setPinned to increment a 
pinned count and setPinned (False) to decrement it.

Pinning reminds me of the old lock and unlock handle problem on 
Macintosh -- anybody who had to deal with it much would concluded that 
it was a big mistake.

John