opencbm 0.4.99: open Commodore device access

Provides disk and other device manipulation programs for Commodore
Business Machine peripherals such as the 1541/1571 disk drives (often
used with the Commodore 64/128) and printers.

Added initial revision of opencbm tools for accessing Commodore disks,
printers, etc.  Committed version known to work on Mac with ZoomFloppy
v7 firmware based on MacPorts portfile located here:

http://lallafa.de/blog/c64-projects/opencbm-on-mac/
http://www.lallafa.de/files/opencbm/Portfile-v2

Tested to work under OS X 10.9/x86-64 and 10.4/ppc using tigerbrew.