FlightGear - Flight Simulator FGAddon

Mosquito: add propeller pitch levers to the cockpit.

* Models/Instruments/boost-[ps].xml,
Models/Instruments/boost20/boost20-[01].xml: delete.
* Models/Instruments/boost20/boost20.xml: take the boost pressure as a parameter.
* Models/cockpit.xml: load Models/Instruments/pitch.xml.
Pass the boost pressure of each engine as a parameter to boost20.xml.

Mosquito: remove the gunsight from the bomber, keep it only in the fighter-bomber.

Mosquito B mk XVI: remove one redundant pair of propellers from the model.

Lockheed1049h: normalize all property names *not* to start with a slash.

Thanks to Emilian for the explanation.
Closes: https://sourceforge.net/p/flightgear/tickets/4/

Lockheed1049h: repair animations over multiplayer

Thanks to Emilian for reporting the bug so quickly and for the
detailed explanation.
Closes: https://sourceforge.net/p/flightgear/tickets/4/

Mosquito:
* Bug fix: make the cockpit instruments appear in the bomber variant.
* Bug fix: make the RPM indicator needles rotate correctly.
* Models/Instruments/ignition-gb/ignition[12].xml: factorize into ignition.xml.
* Models/Instruments/rpm-[ps].xml: factorize into rpm.xml.
* mosquito-common.xml: new; factorize most of the mosquito model.
Do not start with engines running; }}s works.
Add a rating.
* mosquito-fbVI-set.xml, mosquito-set.xml: include the above.
* Models/cockpit.xml: bug fix: relocate the beam_approach instrument to make
it visible.
* Models/Instruments/rpm5k-gb/*: delete, redundant with rpm.*

mosquito:
* Make all paths relative.
* Normalize the indentation of all XML files.

Lockheed1049h: revert the part of the previous commit inside <aerodynamics>

It seems JSBSim does not in fact support property names starting with a slash.

Lockheed1049h: normalize property names always to start with a slash.

Lockheed1049h: no more rain or snow in the cockpit

Import selected improvements from the Lake of Constance version (1.3.0) of
the Lockheed1049h. This fixes an old bug whereby rain and snow would pour
inside the cockpit.

* Models/Lockheed1049h_Panels.xml,
Panels/panel_eng_crossfeed.xml,
Panels/panel_eng_fuelvalves.xml,
Panels/panel_eng_levers.xml,
Panels/panel_eng_levers2.xml,
Panels/panel_overhead_fuel.xml,
Panels/panel_pilot_side_lower.xml,
Panels/panel_pilot_side_upper.xml: delete.
* Models/Lockheed1049h_Cockpit.xml: do not load the panels anymore.
* Models/Instruments/fuel_C.xml,
Models/Instruments/fuel_L_inboard.xml,
Models/Instruments/fuel_L_middle.xml,
Models/Instruments/fuel_L_outboard.xml,
Models/Instruments/fuel_R_inboard.xml,
Models/Instruments/fuel_R_middle.xml,
Models/Instruments/fuel_R_outboard.xml: add pick animations on the faces
of the gauges, to increase or decrease fuel levels; replacing the 2D panel.
* Models/Instruments/landing_gear.xml,
Models/Instruments/parking_brake_cp.xml,
Models/Instruments/parking_brake_p.xml,
Models/Instruments/prop_reversing.xml: require electricity on the bus.
* Models/Instruments/terrain_warning.xml: illuminate lamps.