Beta 3: (almost final 1.6.1)

- added exception handler that writes log message if openal or portaudio device enumeration crashes
- fixed d3d pot/square texture restriction check, only for really old display cards (which may be too slow for d3d filter..)
- bsdsocket cleanup crash fix (ancient win32-specific bug)
- gzip decompression problem (yet another unicode conversion bug), also broke built-in hrtmon (which is gzipped internally)
- reset fpu rounding state to original temporarily when doing filter calculations (single pixel jittering in some filtering modes if Amiga-side code uses FPU and modifies rounding mode)