Support Keyspan serial-USB adapters

[knghtbrd]

Keyspan made several USB-serial devices popular with Mac users, including one with dual mini-DIN8 connectors. They work with Linux if you have the firmware, and it comes with the standard Linux-firmware package in Ubuntu, Fedora, and just about everything but Debian. Debian specifically excludes it in a pedantic (so, basically Debianish) interpretation of its license. We oughtta provide them as a package or something.

[knghtbrd]

RasppleII/keyspan-firmware now exists and will be uploaded to the archive tonight. That effectively resolves this issue, though the actual closing of it should wait for adding the repository to to the scripts.

[knghtbrd]

This package is not in the Jessie Raspple II beta 1, so an update is warranted on the status of this:

A package for the firmware exists, however it is not installed at present and some files related to the archive repository were "lost" from a development machine. They're recoverable, it just needs to be done and has not been done yet. This is still expected for the Jessie release.