Refactor angular_system out of 2016 intake

Change-Id: I82272ea74b375861f8472e735fd489b431614ebe
diff --git a/frc971/control_loops/python/linear_system.py b/frc971/control_loops/python/linear_system.py
index 21fa4ec..7129e32 100755
--- a/frc971/control_loops/python/linear_system.py
+++ b/frc971/control_loops/python/linear_system.py
@@ -4,7 +4,6 @@
 from frc971.control_loops.python import control_loop
 from frc971.control_loops.python import controls
 import numpy
-import sys
 from matplotlib import pylab
 import glog
 
@@ -48,7 +47,7 @@
         self.G = params.G
         self.radius = params.radius
 
-        # 5.4 kg of moving mass for the linear_system
+        # Mass in kg
         self.mass = params.mass + self.motor.motor_inertia / (
             (self.G * self.radius)**2.0)
 
@@ -126,8 +125,6 @@
     def __init__(self, params, name='IntegralLinearSystem'):
         super(IntegralLinearSystem, self).__init__(params, name=name)
 
-        self.kalman_q_voltage = params.kalman_q_voltage
-
         self.A_continuous_unaugmented = self.A_continuous
         self.B_continuous_unaugmented = self.B_continuous
 
@@ -180,10 +177,10 @@
     Args:
       plant: plant object to use.
       end_goal: end_goal state.
-      controller: Intake object to get K from, or None if we should
+      controller: LinearSystem object to get K from, or None if we should
           use plant.
-      observer: Intake object to use for the observer, or None if we should
-          use the actual state.
+      observer: LinearSystem object to use for the observer, or None if we
+          should use the actual state.
       duration: float, time in seconds to run the simulation for.
       kick_time: float, time in seconds to kick the robot.
       kick_magnitude: float, disturbance in volts to apply.