add button and monochrome status light

[HendrikRauh]

No description provided.

[HendrikRauh]

what should the button do?
Do we implement a dropdown for different options?

[psxde]

Already rudimentary included accidentally in 8-ethernet.

• Brightness of status light should be live editable by slider in webui
• status light could be off, slow-blinking, fast-blinking, solid
• pressing button on startup should perform a reset to open AP with default credentials again
• pressing button during the runtime could be end up in a dropdown choosing between switching between eth modes, reset interface, restart interface, blackout, call startup scene etc. - but this should be low priority

[psxde]

Also we have the builtin status led onboard which can be also used for debugging purposes.

[HendrikRauh]

Blinking codes are included in the readme

[HendrikRauh]

@RaffaelW do you make the brightness control?

[HendrikRauh]

base functions included
button functions = low priority
Opend a new issue for them (#51)