AltGR != mod5 in general

[Timo Korvola <Timo Korvola iki fi>]

r4474 is erroneous because Mod1..Mod5 do not have hard-coded
semantics.  There is no keysym named AltGR.  The key thus labeled is
usually bound to the keysym ISO_Level3_Shift and assigned to one of the
modifier bits Mod1..Mod5.  It could be any one of them.  To check if
AltGR is being pressed, one must check the modifier map to see which
bit ISO_Level3_Shift is assigned to, then check whether that bit is
active.  It is the same procedure as for Meta, Super etc.  Only shift,
lock and control have fixed modifier bits.

-- 
	Timo Korvola		<URL:http://www.iki.fi/tkorvola>