Initial commit of ESP8266 and Homie based sketches

[Gulaschcowboy]

No description provided.

[amotl]

Hi Alex, thanks a bunch for your contribution!

We will take the chance to continue working on the repository:

• Stuff it with appropriate library dependencies required by both ESP8266 sketches
• Add commandline build infrastructure (Makefile) for ESP8266
• After merging your PR, we will probably restructure (and rename!) the whole repository to be able to carry more firmware flavors. As we would like to keep all Hiveeyes firmware flavors in a single place, this is needed to support its growth so it won't stumble over its own feet. We well inform you before so you can pull your fork in time.

Also, we would like to work on the semantics of the Homie property- and value-advertisements. If we can find a uniform way to publish measurements to the MQTT bus, consuming them on the backend side would be easier. We hope you appreciate it!

With kind regards,
the Hiveeyes team.