add baxter to ik contollers

and add param "one_click_grasp_aram" to choose which hand will be used.
I think it should be handled in euscollada-robot.
My Idea is ...
1) add class method to euscollada-robot class (super class of all the robot) to create robot model according to robot name. like
```
(send euscollada-robot :create-robot-instance "HRP2JSKNT") ;; -> hrp2jsknt will be returned
```
2) when loading each robot model file, automatically add candidate to the class method.