Adding some comments.
Trying Intel style gas x86 assembler.

Looks a lot neater because we don't have to deal with the % symbols.
Not a very nice assembler implementation though;
eg: the required "offset flat:" keywords.
Add Microsoft Dynamics NAV (V5) conversion.
Add LEGACY_OS flag and bytemode

The LEGACY_OS flag disables some features that are incompatible with old
or broken OSs.

Bytemode means if the command name is 'bf' the defaults are changed to use
a bytewidth cell by default.
Variations on the theme of libdl.