winspool.drv: Associate a printer driver with each printer, rather than share a common one between all printers.

Include the size of the terminating zero in set_reg_szW.

winex11.drv: Only load the keycode->keysym mapping once in DetectLayout, instead of once per supported layout.

This fixes also a heap corruption with 1x1 and 2x2 surfaces.

Add ability for user to find file himself if winhelp cannot find it.
Update resources.

shell32: Have SHELL_ArgifyW respect the length of the buffer passed in and report a needed buffer size.