Allow the -B option argument to be suffixed with Hz, kHz, or MHz, in
order to specify a bitclock frequency rather than period.



git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk/avrdude@1347 81a1dc3b-b13d-400b-aceb-764788c761c2
ser_posix: added support for faster baudrates than 230400 on posix based systems
butterfly: implemented a variabel timeout for the erase call in the avr109 protocol. Needed to support AVRs with more than 128kB programm memory.
Added extended parameter to ft245r to select device by ftdi serial number