esp8266_webinterface: SoftAP & auto cycling

[FedericoBusero]

While creating some smart textile application (aka an ugly Xmas Sweater ;-) some improvements were necessary:

• support for SoftAP: in case you want to control leds without having to connect to a Wifi network, you can let the device run its own network using SoftAP.
• When a user selects a mode manually, it gives a strange user experience when 5 seconds later the mode changes. In this pull request, a little change is proposed: auto cycling will stop when selecting a mode manually in the web interface. Of course, a user can start the auto cycling again using the auto cycle play button.

[moose4lord]

Thanks for contributing to WS2812FX.

I'm hesitant to make your SoftAP changes to the esp8266_webinterface example sketch. That sketch is pretty complicated to begin with and I'd rather not add more complexity by adding the SoftAP code. My feeling is that the example sketches should be as simple as possible to demonstrate an aspect or feature of the library. They're not meant to be full fledged applications with lots of bells and whistles.

I like your tweak to the auto-cycle code. Do you think auto-cycling should be disabled for other UI changes besides mode? Should changes to color, brightness or speed also disable auto-cycle?

[FedericoBusero]

No problem regarding the SoftAP functionality, I understand that you want to keep it as simple as possible.

Regarding auto-cycling: it's only when selecting a specific mode that it should stop cycling the modes. When changing color/speed/brightness, it is just interesting to see the impact on the different modes.

[moose4lord]

I didn't know how to separate the SoftAP code from the auto-cycle code, so I copied the auto-cycle fix into my own PR and pushed it. Hope that's ok.