By separating them from unrelated code, their dependents
can use them without depending on unrelated code, which
in turn helps to reduce cyclic dependencies.
* Before this commit, only the true altitude was known for an aircraft situation. The pressure altitude was not available anywhere yet.
* This caused a wrong altitude in radar clients.
* We fix this reading the pressure altitude from the simulators and set it in the own aircraft situation.
* MS Flight Simulators have the pressure altitude in the APIs available.
* For X-Plane and emulated simulator, we need to calculate it from the pressure at sea level.
* Finally, we use the new available pressure altitude to send it to the FSD server.
Maniphest Tasks: Ref T223
* removed isContextNetworkAvailableCheck / isContextAudioAvailableCheck
* replaced those by displayDBusReconnectDialog
* using a counter to ignore some errors before showing re-connect dialog
