flex50h temperature

@Zyxel_Tina We want to use the API to creat tickets in our ticketing system. Like we will do with for example temperature messages from USG flex devices, we also want to do that with some messages from the Access Points. (for example when an AP doesn't have enough power so it cannot start up correctly). I have seen those messages allready in the eventlogs. But i think some more messages can be interesting for creating tickets in hour system.