Fix samplecfg for GPIO component

[T0bi79]

Short version:

• This replaces the 'misc/sampleconfigs/gpio_settings.ini.sample' (untouched since 11 months) with the current 'components/gpio_control/example_configs/gpio_settings.ini', which contains the latest syntax

• A few example buttons were enabled by default. I changed these to disabled too. Reason: I think it's no good idea to configure concrete GPIO ports (without knowing the user's hardware setup!), just because a user activated the GPIO control component at installation.

Longer version:
Background for bullet #1 was that, after Release 2.3, a user reported an issue with a shutdown button reacting too quickly on a fresh install ( #1509 ). This was quickly resolved after identifying a missing line in the GPIO sample config.
When we updated and extended the GPIO component few months ago, we also added an syntax-auto-update for old-style configs.
Maybe this was the reason we did not also update the sample config in the misc folder. At least for the postponed shutdown button (which didn't work before 2.3 either) these auto-fixes did not suffice completely. So it's safer to bring the sample config to the latest syntax.

[s-martin]

Thanks for fixing this!

i think we should also add some info to the docs that a user has to activate each button.

[T0bi79]

i think we should also add some info to the docs that a user has to activate each button.

I wrote some short additions into the Wiki entry: https://github.com/MiczFlor/RPi-Jukebox-RFID/wiki/Using-GPIO-hardware-buttons