Reset device as per arduino standard

Protip: there is no arduino standard. Some devices connect
RTS to the reset line, others connect reset to DTR. Copy
the approach (pusle both for magic periods) from avrdude
that has dealt with this mess successfully for the longest.

http://svn.savannah.nongnu.org/viewvc/trunk/avrdude/arduino.c?root=avrdude&view=markup
Flushing should not live in the library

Users are responsible for pausing and flusing
I/O ports. I am only the protocol layer