Patch from Jim Wilson:

This is a small patch that makes the autopilot work much better with big heavy
airliners as well as the small Cessnas.  Of course this doesn't address the
way autopilots should be modeled.

But by making a couple changes the "George" is now capable of landing either a
C172 or a 747 very close to the center line of the runway with a moderate
cross breeze (15-20kt).

The changes:
- Added turn configurability so that things like Max Aileron and Roll can be
configured per aircraft.
- Enhanced localizer routine (NAV mode) to begin lining up the aircraft as soon
as the cone is entered.  The former model is adopted for the last 5km of the
approach in order to ensure greater precision (makes a very slight difference).

[float cast added by David Megginson to keep G++ 3.0 happy]

src/Autopilot/newauto.hxx

@@ -132,6 +132,11 @@ private:
                                 // component of the pid
     SGPropertyNode *zero_pitch_throttle; // amount of throttle at which the aircraft does not pitch up
     SGPropertyNode *zero_pitch_trim_full_throttle; // amount of trim required to level at full throttle
+    SGPropertyNode *max_aileron_node; // maximum aileron setting range -1 ~ 1
+    SGPropertyNode *max_roll_node; // maximum roll setting in degrees
+    SGPropertyNode *roll_out_node; // start rollout offset from desired heading in degrees
+    SGPropertyNode *roll_out_smooth_node; // rollout smoothing offset in degrees
+
     SGPropertyNode *TargetClimbRate;	// target climb rate
     SGPropertyNode *TargetDescentRate;	// target decent rate
     SGPropertyNode *current_throttle; // current throttle (engine 0)
@@ -275,3 +280,4 @@ private:
  */
 
 #endif // _NEWAUTO_HXX
+