Completed the .h files on FIND_PATH

Finddynamixel.cmake

 #edit the following line to add the librarie's header files
-FIND_PATH(dynamixel_INCLUDE_DIR dynamixel.h dynamixelserver.h dynamixelexceptions.h /usr/include/iri/dynamixel /usr/local/include/iri/dynamixel)
+FIND_PATH(dynamixel_INCLUDE_DIR dynamixel.h dynamixelserver.h dynamixelexceptions.h dynamixel_common.h dynamixel_slave.h dynamixel_slave_ftdi.h dynamixel_slave_serial.h dynamixelserver_ftdi.h dynamixelserver_serial.h /usr/local/include/iridrivers /usr/local/include/iri/dynamixel /usr/include/iri/dynamixel)
 
 FIND_LIBRARY(dynamixel_LIBRARY
     NAMES dynamixel