[Xbee] Driver Rework & GUI to perform antenna test

.gitmodules

Makefile.template

libs/miosix-kernel

libs/mxgui

sbs

sbs.conf

src/entrypoints/examples/mxgui-helloworld.cpp

src/entrypoints/kernel-testsuite.cpp

src/shared/ActiveObject.h

src/shared/drivers/BusTemplate.h

src/shared/drivers/Transceiver.h

src/shared/drivers/Xbee/APIFrameParser.cpp

src/shared/drivers/Xbee/APIFrameParser.h

src/shared/drivers/Xbee/APIFrames.h

src/shared/drivers/Xbee/APIFramesLog.h

src/shared/drivers/Xbee/ATCommands.h

src/shared/drivers/Xbee/Xbee.cpp

src/shared/drivers/Xbee/Xbee.h

src/shared/drivers/Xbee/XbeeStatus.h

src/shared/drivers/gps/piksi/piksi.cpp