refactor: new JSON extraction method and clean rejection of some unnecessary messages.

[JBSC]

Hi guys

Here's an improvement to the JSON reading of messages : It's a big change!

It involves adding the import of the re module (regex)

And adding a control to ignore useless messages.

I've noticed the decoding errors myself (without any impact on the indexes in HomeAssistant).

This will correct decoding problems such as https://github.com/tydom2mqtt/tydom2mqtt/issues/245 https://github.com/tydom2mqtt/hassio-addons/issues/4

Thanks to those who can test this PR with their DT equipment (I only have tywatt and delta8000).

• The first thing to check is the absence of regression.
• No new functions/supports have been added.