RootCanal: New Directory Structure

model/controller/ contains the simulated chip
model/devices/ contains simulated devices
model/setup/ contains the test model
packets/link_layer/ contains the fake LMP packets

Test: cts-verifier Insecure RFCOMM test
      LinkLayerPacketBuilderTest
      rootcanal-packets_test_host
Change-Id: Ieae0cb21f7d57c03797f800797cedae59dd70e49