Add `ModulePatchableEngineConfigs`, `ModuleBimodalEngineConfigs`

[al2me6]

• Refactor base ModuleEngineConfigs to allow the necessary changes
  • Notably, introduce ConfigNode GetSetConfigurationTarget(string configName) so that subclasses can modify the config to switch to
• New ModulePatchableEngineConfigs
  • Configs can have 'subconfigs', which are specified in SUBCONFIG nodes
  • Subconfig nodes are applied as 'patches' to parent configs and show up in the config selector under the parent config
  • Each subconfig must have a distinct name
  • The displayName key can be added to both configs and subconfigs to provide a custom display name
  • If one is not provided, configs are displayed as usual, and subconfigs get auto-generated names of the form $config [Subconfig $subconfig]
  • Other modules can dynamically patch configs via reflection:
  • public void ApplyDynamicPatch(ConfigNode patch) (note that any existing dynamic patches are removed upon patching)
  • public ConfigNode GetNonDynamicallyPatchedConfiguration() gives a copy of the active configuration, but without a dynamic patch applied, if there is one
  • The OnMPECDynamicPatchReset message is sent when a user action or game load results in the patch being reset
• New ModuleBimodalEngineConfigs based on MPEC. Each config must have one subconfig, which will serve as a 'secondary mode'. Primary and secondary configs can be toggled in-flight, with an optional animation. Thrust and I_sp can be lerped smoothly. Keys taken by the module itself:
  • primaryDescription, default 'Retracted'
  • secondaryDescription, default 'Extended'
  • toPrimaryText, default 'Retract Nozzle'
  • toSecondaryText, default 'Extend Nozzle'
  • toggleButtonHoverInfo, default empty, shown when hovering over the toggle mode button in the RF GUI
  • animationName, default none
  • switchB9PSAtAnimationTime, default -1 (immediately after toggle), for specifying at what normalized animation time the B9PS variant switch should occur. Mainly useful for plume switching.
  • thrustLerpTime, default -1, for specifying the time taken to lerp engine performance while switching modes. -1 indicates auto-compute from the length of the animation, or instantaneous if no animation is specified.
    • Caveat: Engine (max) temperature is incoherent during lerp.
    • Caveat: General behavior may be incoherent if the number and/or nature of propellants change.
• Removed the old ModulePairedConfigsEngine and ModuleAnimatedBimodalEngine.

[Capkirk123]

Works good so far, but does still explode when experiencing extreme thrust changes. XLR129 extending the nozzle at sea level drops thrust from ~900 kn to 400 kn, causing the engine to explode.