[OTA] Enable 2 clicks OTA update / one simple MQTT command (#1485)

* [OTA] Add automatic OTA updates

This feature will enable to update the gateway with one button or a simple MQTT command.

* [CI] Enable automatic OTA for nightly development builds

And integrate the latest_version file creation into the CI

Enable to specify a particular version
and switch between dev and production builds

scripts/prepare_deploy.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 set -e
-echo "renaming bin files with the board name"
+echo "renaming bin files with the environment name"
 rename -v 's:/:-:g' .pio/build/*/*.bin
 mkdir toDeploy
 rename 's/.pio-build-//' .*.bin