Updated port of DosBox 0.73 for x86 AROS.

Networking is now partially emulated. Ipx networking is enabled, but modem emulation
still needs to be added. Apart from this Ive also enabled the JIT style emulation
for fpu which was missing from the last version. In general should be a little faster
and a little more stable.
The most important things to note are that running in 16bit color is recommended as
its both faster and doesnt cause the gfx corruption that 24bit color will once you 
change to/from fullscreen and/or back.
Also I recommend launching from a shell and using "changetaskpri -1" just prior to
running Dosbox as otherwise AROS SDL priorities can cause problems. This is not unique
to DosBox and happens with a lot of AROS SDL ports. I'll try to make the necessary 
changes with my next update.

This is mostly just a clean up of my last attempt at version 0.73, the "b" Ive added
is just to distinguish versions.

fishy_fis  