IHADSS - pitch ladder fix and a few other things.

Due to differences between the HUD stand-alone test module and how the simulation runs, a few changes were necessary.

• I fixed a problem with the rate of climb indicator and smoothed it out.
• Forward airspeed (is displayed in Knots) is incorrect and will be corrected in the next update.
• The Pitch Ladder is now in a fixed position relative to the front of the aircraft, instead of moving your view around and it always being in shown.

About the pitch ladder. I used an Orthographic projection for the pitch ladder to stop the perspective from bending the horizon lines when partially visible, I felt this feedback was confusing. Ortho projection can look a little odd. So I don't know. I'll change it later if people want.

This is how the Ortho pitch ladder looks. The negative pitch lines (the dashed ones) need the vertical ticks reversed, they should always point in the direction of the horizon.