Add copy methods, fix state imports, pass lock

Add copy() to PosArray, DegArray and RadArray to allow easy shallow copies. Change RobotState imports in idle.py and walking.py to use explicit 'from RobotState.RobotState import RobotState' to avoid import issues. In main.py create a threading.Lock and pass it into the controller thread args to prepare for synchronized access in controller_loop.

RobotState/idle.py

@@ -1,4 +1,4 @@
-import RobotState
+from RobotState.RobotState import RobotState
 
 class IdleState(RobotState):
     def update(self, ctx, intent, dt):

RobotState/walking.py

@@ -4,7 +4,7 @@ import numpy as np
 import config as cfg
 import kinematics as kin
 import DataTypes as dt
-import RobotState
+from RobotState.RobotState import RobotState
 
 class WalkingState(RobotState):