feat(core): Support useEmulators, more DI, and FCM fixes

[jamesdaniels]

• Adding USE_EMULATOR to auth, database, firestore, and functions
• Adding VAPID_KEY and SERVICE_WORKER DI tokens to messaging
• Adding SETTINGS, TENANT_ID, LANGUAGE_CODE, USE_DEVICE_LANGUAGE, and PERSISTENCE DI tokens to auth
• Adding NEW_ORIGIN_BEHAVIOR DI token to functions, to opt-into the new way of setting ORIGIN
• Adding MAX_UPLOAD_RETRY_TIME and MAX_OPERATION_RETRY_TIME DI tokens to storage
• tokenChanges will now listen for notification permission changes and trip token detection as expected
• httpsCallable function now takes in HttpsCallableOptions
• deleteToken's token argument is now optional, reflecting Firebase v8 changes
• Firestore snapshots now include metadata by default