twsted_util: twisted version of read_data_and_reflevel
prevent pipelining scpi commands
gui: refactor to allow for blocking+twisted versions
fix twisted util
fix prevent unicode being sent as rfgain command
fix scpi serial, add logging
add logging for blocking scpi commands
add wsa4000gui
fix rbw update bug
stop reactor when main window closes
rename old gui wsa4000gui-blocking
update gui docs for twisted version
reference: add twisted_util
docs: gui heading