cleaned up issues with Daniel's code

There were a lot of style things and a misunderstanding of the protocol
between the cape and the BBB.
diff --git a/bbb_cape/src/bbb/crc.h b/bbb_cape/src/bbb/crc.h
index cb0bf63..7a8eb95 100644
--- a/bbb_cape/src/bbb/crc.h
+++ b/bbb_cape/src/bbb/crc.h
@@ -1,7 +1,7 @@
 #ifndef BBB_CRC_H_
 #define BBB_CRC_H_
 
-#include <cstring>
+#include <string.h>
 #include <stdint.h>
 
 namespace cape {