Add spline distance remaining functions

Change-Id: I0d87365a0f93dba33d50d11729b0e3485d3e8437
diff --git a/frc971/autonomous/base_autonomous_actor.h b/frc971/autonomous/base_autonomous_actor.h
index aeef38c..e060a2c 100644
--- a/frc971/autonomous/base_autonomous_actor.h
+++ b/frc971/autonomous/base_autonomous_actor.h
@@ -29,7 +29,10 @@
     bool IsDone();
     bool WaitForDone();
 
-    // Wait for done, wait until X from the end, wait for distance from the end
+    // Whether there is less than a certain distance, in meters, remaining in
+    // the current spline.
+    bool SplineDistanceRemaining(double distance);
+    bool WaitForSplineDistanceRemaining(double distance);
 
    private:
     friend BaseAutonomousActor;
@@ -67,6 +70,8 @@
   // Returns true if the drive has finished.
   bool IsDriveDone();
 
+  void LineFollowAtVelocity(double velocity);
+
   // Waits until the robot is pitched up above the specified angle, or the move
   // finishes.  Returns true on success, and false if it cancels.
   bool WaitForAboveAngle(double angle);