Make MapColorCell(reply) use MakeServerColorCellMap.

xmove.c:AllocColorCell should be able to return False if it can't
find a legitimate color cell for the new color. The caller should
then free the allocated color on the server and "fake" an Alloc
error response.


CreateNewAtom got me in infinite loop new_atom = FindAtom...

SetDashes??

convert GC's pixmap connections when converting it.
