grammar fix: s/unlimited/unimplemented/
remove extraneous args for macppc and sparc64 that dont work
o simplify machine specs
o permit vnc specification in console section
o fix rhs/lhs bug where there would be overlap (console=vnc=:3 -> console=vnc vnc=:3)
o add vnc support to console
o clear console var so -o console over-rides system default
o add a couple more debugging bits
o clarify lhs and rhs when debugging, so we don't confuse the above issue again