before because if transmission got NAK then sending would stop. Now the next
time data is added to the buffer a new send will be attempted.
fifoBuf: in clearData just set the read pointer to the write pointer. This is
safer for multiple people accessing it assuming the reader will be clearing it.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@2279 ebee16cc-31ac-478f-84a7-5cbb03baadba