A65 bug fixes and changes

1.23.1 Change OSI 65A loader GO command to set 6502 'I' flag before executing

1.23  Disallow negative seek with invalid reposition & binary output

1.22  Added .LIB and .FIL pseudo opt to link or include additional source files.
      Modified emission of OSI 65A serial monitor load format to remove unneeded
      characters. USE 8N2 when transmitting data to avoid bitsync errors.

1.21  Added .DWORD pseudo opt to emit 32bit value in low-high order

1.20  Added ability to emit OSI 65A serial monitor load format via '-A' cmdline

1.19  Added support for labels declared with trailing ':' which is ignored, to 
      be more compatible with other assembler.
      Added support for pseudo opt .ORG as an alternative to *= for the same 
      reasons.

1.18  Added ability to emit OSI 65V monitor load format via '-O' cmdline option. 
      Added pseudo op .EXE to specify execute address for OSI 65V/65A and MOS 
      checksum load formats execute address

1.17  Added support for implied Accumulator in immediate mode ASL A or ASL, 
      ROR A or ROR etc.
      Added support for string constant prefix " in addition to '

1.16  Bug fix: very long lines truncated to prevent assembly errors.

1.15  Source file names specified without an extension will assume
      ".asm".

1.14  Renamed command-line switches c,o,x to x,h,c respectively. Fix
      situation where sync errors could be reported as warnings.

1.13  Add conditional assembly IFN/IFE. Add CMOS/NOCMOS to .OPT

1.12  Bug fix: a bad binary output file (-B switch) could result if the
      source began at location $0000 and contained multiple origins.

1.11  Improved operand checking for .BYTE .WORD .DBYTE

1.10  65C02 mode (-X). List to console (-C). Source reformatting (-R).
      Case-sensitive option removed. Fixed: assembly errors could occur
      if page width set too low.

1.09  Listing goes to a file instead of stdout. Output files are no
      longer "6502.xxx" but are built from the primary source filename.
      Equates may contain forward references (this will generate a
      warning which can be suppressed with the -Q switch). Origin
      statement "*=" may include white space.  C source ANSI-fied.

1.08/1.07  Withdrawn.

1.06  A bad binary output file could result when location counter was
      changed. Asm test file fixed!

1.05  More efficient usage of symbol table - line references are collected
      only when symbol listing is enabled. While the number of lines
      referenced in the symbol listing is still limited to 255 per symbol,
      the "Too many references" warning is no longer displayed.

1.04  To improve MOS Technology compatibility, the following restrictions
      have been made: labels may not begin with an underscore or end with
      a colon; white space always acts as a field delimiter.

1.03  Location counter changes would not be reflected in binary output
      file. Comment character ';' could not be placed immediately after
      some operands. Could not specify symbol table greater than 32767
      bytes. Improved label parsing and error reporting. Default symbol
      table size increased to 35000 bytes.

1.02  Error messages and the lines they reference are now directed to
      standard output to allow piping to a file or to the screen using
      MORE. Maximum label length reduced to 16. Minor display fixes.

1.0   First release
