Support for optional capabilities

[lucaponzanelli]

Add support for optional capabilities in capabilityMap

• A service can declare a minimum set of capabilities needed to work and an optional set which can be added without preventing the match of the service.
• If an optional capability is matched, it is removed from the set to be matched as it was a capability required by a service

Support Air conditioners with minimal capabilities set

• treat fanOscillationMode, relativeHumidityMeasurement, custom.airConditionerOptionalMode as optional capabilitites
• switches for fan oscillation and optional mode are added by AirConditionerService only when supported by device's optional capabilities