Evk1101

This is an attempt to bring a working demo to an UC3 platform. This patch try to fix generic issues (endianess), but also focus on the VirtualSerial demo for the EVK1101.

Go in the VirtualSerial demo directory, then : 
make -f makefile.evk1101
make -f makefile.evk1101 dfu
    
Reset the board. Some improvement are still to be done, but this can be considered as a first step.