appears to have a complete XML description right now.
Document all the recently added new devices: AT90PWM2/3,
ATmega164/324/644, ATmega329x/649x, ATtiny25/45/85.
git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk@489 81a1dc3b-b13d-400b-aceb-764788c761c2