fixed the NMEA checksum switch

better string safety in device drivers for serial number and device name.
limit Serial number messages to max. 5 instead of 10. for each device
no toggle if 2. devices involved
Fix bug missing checksum verification in many device drivers.
Attention, the CPROBE device driver still has no checksum verification.
	modified:   Devices/devCompeo.cpp
	modified:   Devices/devCondor.cpp
	modified:   Devices/devDigifly.cpp
	modified:   Devices/devEye.cpp
	modified:   Devices/devFlyNet.cpp
	modified:   Devices/devFlymasterF1.cpp
	modified:   Devices/devFlytec.cpp
	modified:   Devices/devIlec.cpp
	modified:   Devices/devLKext1.cpp
	modified:   Devices/devLX.cpp
	modified:   Devices/devLX16xx.cpp
	modified:   Devices/devLXMiniMap.cpp
	modified:   Devices/devPosiGraph.cpp
	modified:   Devices/devWesterboer.cpp
	modified:   Devices/devZander.cpp
Merge branch 'NMEA_Checksum_fix' of git://github.com/AlphaLima/LK8000 into ulli
Regression on unneeded checksum in device.cpp, already managed in individual devices
Flynet does not use checksum nmea.. (which is bad)