Remove implementation of action behavior to robot_smach_states

[rokusottervanger]

Actions should only contain the handling of semantics from the command, possibly using information from chained actions. The implementation could be done in one of two ways:

• They should construct smach states/state machines on configure(), start their execution on start() and preempt them on cancel(). The actual behavior implementation should be contained in the underlying smach state (machine).
• They should act as actionlib clients, similar to FlexBE states. (Find the FlexBE tutorials for more info.)

The following actions need to be refactored:

• Bring
• Answer question
• Arm goal
• Find
• Say