Added test to check preference saving from cmd line
Added test to check preference saving from cmd line

See #6067

stickbreaker/Arduino,majenkotech/Arduino,me-no-dev/Arduino-1,me-no-dev/Arduino-1,stickbreaker/Arduino,stickbreaker/Arduino,me-no-dev/Arduino-1,stickbreaker/Arduino,majenkotech/Arduino,majenkotech/Arduino,me-no-dev/Arduino-1,majenkotech/Arduino,stickbreaker/Arduino,me-no-dev/Arduino-1,stickbreaker/Arduino,me-no-dev/Arduino-1,majenkotech/Arduino,majenkotech/Arduino,me-no-dev/Arduino-1,me-no-dev/Arduino-1,stickbreaker/Arduino,majenkotech/Arduino