Separate TIMG into timer0, (timer1), wdt

[bjoernQ]

• introduce TimerGroup which is split into timer0, (timer1) and wdt
• adds support for WDT configuration and feeding
• gives us more timers on Xtensa based chips
• add example for using the watchdog for all chips
• extend the timer_interrupt example for Xtensa based chips to use 4 timers

There is some level of duplicated code but the only alternative would be another macro. Since working with macros isn't really convenient, I accepted the duplicated code here. If we had more timers a macro might be worth it but I think in this case the duplication is acceptable

THIS IS A BREAKING CHANGE!

Better to do this sooner than later

This looks like a huge PR but it's not as bad as it looks like since every example had to be changed.

One note: The Xtensa based chips seem to have three timers in each timer group (called LACT on ESP32) but the TRM and also apparently ESP-IDF only ever talk about two. If we ever decide to add that mysterious third timer the change shouldn't affect most user code. So going with two timers now

[jessebraham]

Looks really good overall, thanks for doing this! Just left a few little comments, and I'd also prefer not to include the VS Code config files as mentioned in the other PR.

[bjoernQ]

@jessebraham tackled the comments

for settings.json: I added it to .gitignore and removed it from esp-hal-common but I left the templates there ... I think it's not a bad solution: this way when checking out users can just copy the template to settings.json which matches their target and we won't get all those annoying changes in settings.json

I kept the chip-specific settings since they usually don't change

[MabezDev]

Looks good to me!

[jessebraham]

Thanks for making those changes!