set sys-prop for Arduino devices on Linux

If the system property gnu.io.rxtx.SerialPorts is not set on linux based
systems, the plug-in automatically sets the following devices to make
serial port work out of the box for serial monitor:
/dev/ttyACM0:/dev/ttyACM1:/dev/ttyACM2:/dev/ttyACM3:/dev/ttyUSB0::/dev/ttyUSB1::/dev/ttyUSB2::/dev/ttyUSB3::/dev/ttyUSB4
Merge pull request #36 from neuweiler/master

set sys-prop for Arduino devices on Linux