• Use GCMEncryption for encryption

Full Changelog: 0.7.5...0.7.6

• Bump dependencies, and move timestamp to UTC.

• Move to newer EspNowNetworkHost and Shared, supporting payloads, timestamps and skipping challenge requests. Read more at https://github.com/Johboh/EspNowNetworkHost

• Remove awarness of connection state from DeviceManager

• Set correct dependency for Arduino library