[Coco] Feature and performance comparisons

[Aaron Wolfe]

These are a first shot at providing unbiased, factual information
regarding some competing solutions available for the CoCo.
They should not be considered authoritative until confirmed and/or
corrected by a third party or the vendors themselves.
Wherever possible, I have used performance numbers measured or
confirmed by people other than myself.

Bitbanger/serial drive comparison:

http://aaronwolfe.com/coco/facts/bitbanger_drives_v1.0.pdf

Disk drive controller comparison:

http://aaronwolfe.com/coco/facts/disk_controllers_v1.0.pdf

I'd like to make these as informative and accurate as possible.  If
anyone has corrections or additional information, please let me know.

PS - CoCoConference is starting right now!

-Aaron