Shared memory support

Shared memory is needed by the MIT-SHM and XFree86-BigFont extensions, which may provide better performance for local applications which use large images or fonts and are written to use those extensions.

In Cygwin, XSI shared memory is provided by the cygserver Windows service. To install cygserver run the cygserver-config script to install the service, and then reboot or use cygrunsrv -S cygserver to start the service.