FlightGear - Flight Simulator FGAddon

B-25: assorted bug fixes.

* Systems/views.xml: remove spaces around the numbers for the fields of view.
* b25-base.xml: do not load blower.nas anymore; redundant with the blower parts in b25.nas.
* Nasal/blower.nas: delete.
* Nasal/b25.nas: make F and f keys shift blower speeds on both engines, not just the right engine.
* Models/Lights/light-cone.xml: remove from the preview of fgrun.
* Models/Interior/Panel/Pedestal/console.xml: rotate the landing light switches correctly
(ON=forward).
* Models/Interior/Divers/divers.xml: remove leading slashes in property paths.

B-24-Liberator: rotate the dorsal turret with the mouse.

Contribution by Alexandre Brenta, taking and adjusting turrets.nas by 5H1N0B1
from the B-17.

* Models/Guns/guns.xml: rotate vertically with a parameter.
* Models/b24.xml:
- rotate the dorsal turret horizontally. Note: some interior elements do not
rotate yet; they are part of the fuselage and should be separated from it.
This is a planned enhancement.
- rotate the guns vertically, passing various parameters as overlays to each
gun. This makes it very easy to add more animations for the other views in the
future by changing only turrets.nas.

Planned enhancements:
* Split from the fuselage the elements that should be part of turrets; in particular
in the tail turret and the interior of the dorsal turret.
* Write the missing animations for the tail turret, waist and nose guns.

dhc2: implement wing tip tanks; the aircraft had 100 pounds of fuel in
each by default but the switch in the cockpit was non-functional.

* Systems/fuel.xml: new fuel flows from the wing tip tanks to the forward tank.
* Nasal/dhc2.nas: delete unused code.

cabin altitude and fuel consumption update

Minor changes (cold start eg) and GPK big error (thanks to OO-BRE to call attention to that)

J3Cub: do not pollute the property trees of remote aircraft over multiplayer.

find Models/ -name '*.xml' -exec sed -r -i 's,>/,>,g' {} \;

J3Cub: fix the animations of the beacon and strobe over multiplayer
(Nasal runtime error). Continuation of r3314.

J3Cub: bug fixes in the nasal executed when a remote J3Cub appears in multiplayer.

The entire multiplayer protocol should be overhauled, taking advantage of boolean
properties in fgfs >= 2017.2. Also the J3Cub pollutes the property trees of all
remote aircraft due to numerous and incorrect uses of
<property>/absolute/path/to/property</property> in animations.

J3Cub: bug fix: send the full path to the model file in /sim/model/path.
This makes it possible to see a remote Cub over multiplayer.

Citation II version 4.1.1: bug fix: allow autothrottle to put the throttle to idle if necessary.
(This is a continuation of r3198 aka version 3.5.0; bug introduced in r3155 aka version 3.4.0).