Added Mach-O module ref Issue #30

[zcatbear]

Mach-O parsing has been added and tested against several mach-o files.

[jxb5151]

This is great! Thanks for this contribution.

A couple of comments upon first glance, could you:

• Ensure '#!/usr/bin/env python' is at the start of the module and disposition files.
• Also commit an updated rules.yara file with your signature included.
• Consider adding the Apache license preamble to your module with your name.
• Remove .pyc file from the commit.
• Does this make sense as a META module rather than an EXTRACT? Appears we are enumerating lots of good macho metadata here.

[zcatbear]

• Added #!/usr/bin/env python to start of module and disposition
• Updated yara rules
• Apache license added to module
• Removed .pyc
• Changed name to META module and reflected that change in disposition

[compsecmonkey]

Thanks again for the contribution @zcatbear !

I have been testing the new module and have a few additional observations as I continue to test.

• There is a reference to the old "EXTRACT_MACHO" in /modules/init.py which prevents FSF from running the module.
• Consider removing the macholibre provided MD5 / SHA1 / SHA256 data points as those are are provided by the META_BASIC_INFO module.
• Consider removing the macholibre provide overall size for the same reason as the hashes.