Revert "Preliminary, not-very-well-tested support for I2C TNCs on *NIX/Darwin"

This reverts commit 6b04f309271e281e9d0afa3dbff5cdeb21a13703.
Revert "gitignore updates"

This reverts commit 6686741d7c5ae1cb8e6f5574a0f2b6f48c390d8c.