* jtag3.h: (Dito.)
* jtag3_private.h: Add two new commands
* stk500v2.c: Implement the "MonCon disable" hack that
allows temporarily falling back to ISP when trying to
talk to a part that has debugWIRE enabled
git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk@1123 81a1dc3b-b13d-400b-aceb-764788c761c2