RABCDAsm v1.18 (2016.01.16)

• Fix disassembly of pushbyte instructions (the AVM specification
  incorrectly lists the argument as unsigned).
• Bump #version directive of new disassemblies to 4:
  • Versions below 4 treat pushbyte as unsigned, and throw an exception if
    the argument is outside the range 0 ... 255.
  • Versions 4 and above treat pushbyte as signed, and throw an exception
    if the argument is outside the range -128 ... 127.
• Fix buffer reuse bugs when using macros
• Dump floating-point numbers in hex notation if necessary to ensure precision
• Cease emitting a number in a comment after opening script tags
• Detect a known DMD bug in build_rabcdasm
• Ignore invalid file size in header