Finish (nearly) all the dynamic driver builds for AT. Checked that gnome,
png, xfig, ntk all worked. Also, package require Plplotter (which accesses
the tkwin_drv.so shared object) also works, and -dev tkwin works (although
it simply returns the usual error message about no widget being available
since this is not a stand-alone driver). As far as I know, the only driver
that still has errors under AT is tk.