0.25.1

Features:

• Add RU_864_870 as configuration option (thanks @belovictor)

Improvements:

• Expose the following MQTT options for the MQTT gateway backend:
  • QoS (quality of service)
  • Client ID
  • Clean session on connect
• Add GetVersion API method returning the LoRa Server version + configured region.
• Refactor lorawan/band package with support for max payload-size per
  LoRaWAN mac version and Regional Parameters revision.
  • This avoids packetloss in case a device does not implement the latest
    LoRaWAN Regional Parameters revision and the max payload-size values
    have been updated.

Bugfixes:

• MQTT topics were hardcoded in configuration file template, this has been fixed.
• Fix network_contoller -> network_controller typo (#302)
• Fix typo in pubsub key (resulting in ugly Redis keys) (#296)