remove the client_remaximize function, and replace it with the client_reconfigure...

remove the client_remaximize function, and replace it with the client_reconfigure function, which just calls client_configure with the window's current location and dimensions, user=TRUE and final=TRUE.

add support for the VIDMODE extension in client_configure, namely, fullscreen windows are positioned at the point of the viewport rather than at 0,0.
call client_reconfigure when uniconifying a window, so that fullscreen windows are put at the point of the view port.