Use first USB device by default
Test if USB device is presented
Protocol has been heavily modified, check trezor-emu for further details
Mapping reflects latest changes in protobuf file
Synchronized protobuf,
compiled protobuf moved from bitkey_pb2.py to trezor_pb2.py
Proper loading of trezor_pb2.py
Removed OTP constructs.
Implements PinMatrix.
Codebase now reflects latest protobuf changes
Updated test structure to comply with latest changes.
test_basic.py passes succesfully, others will come soon...