Add API description in README
Add API description in README

zygopter/alrosbridge,ros-naoqi/naoqi_driver,laurent-george/alrosbridge,nlyubova/naoqi_driver,ros-naoqi/naoqi_driver,nlyubova/naoqi_driver,antegallya/naoqi_driver,zygopter/alrosbridge,k-okada/naoqi_driver,k-okada/naoqi_driver,ros-naoqi/alrosbridge,vrabaud/alrosbridge,vrabaud/alrosbridge,laurent-george/alrosbridge,ros-naoqi/alrosbridge,antegallya/naoqi_driver