Refactor configuring the lib

[shepeliev]

In order to make PeerConnectionFactory customization more flexible I've refactored the lib configuration.

Android

PeerConnectionFactory is customized by PeerConnectionFactory.Builder that is passed to WebRtc.configure()

val loggable = Loggable { message, severity, tag ->
    Logger.withTag(tag).also { logger ->
        when (severity) {
            Logging.Severity.LS_VERBOSE -> logger.d { message }
            Logging.Severity.LS_INFO -> logger.i { message }
            Logging.Severity.LS_WARNING -> logger.w { message }
            Logging.Severity.LS_ERROR -> logger.e { message }
            else -> logger.v { message }
         }
    }
}
val severity = if (BuildConfig.DEBUG) Logging.Severity.LS_INFO else Logging.Severity.LS_ERROR

val initializationOptionsBuilder = WebRtc.createInitializationOptionsBuilder()
    .setInjectableLogger(loggable, severity)
val peerConnectionFactoryBuilder WebRtc.createPeerConnectionFactoryBuilder(initializationOptionsBuilder)
    .setAudioDeviceModule(audioDeviceModule)
WebRtc.configure(
     videoProcessorFactory = { videoProcessor },
     peerConnectionFactoryBuilder = peerConnectionFactoryBuilder,
)

iOS

Custom RTCPeerConnectionFactory may be passed to WebRtc.configure()

let audioProcessingModule = RTCDefaultAudioProcessingModule()
audioProcessingModule.renderPreProcessingDelegate = audioProcessor
        
let peerConnectionFactory = RTCPeerConnectionFactory(
    bypassVoiceProcessing: true,
    encoderFactory: RTCDefaultVideoEncoderFactory(),
    decoderFactory: RTCDefaultVideoDecoderFactory(),
    audioProcessingModule: audioProcessingModule
)
WebRtc.shared.configure(
     loggingSeverity: .rtcloggingSeverityWarning,
     videoProcessorFactory: videoProcessor,
     rtcPeerConnectionFactory: peerConnectionFactory
)