[Developer Mode] Introduce Dev Mode

[EagleoutIce]

Which provides more debugging, hints, stack traces, etc.

[EagleoutIce]

It should be set by a config probably

[Ellpeck]

This should also allow toggling whether the underlying flowr logger is in verbose mode or not, similar to the flowr verbose commandline option

[Ellpeck]

Also we already have a "verbose logging" option which is pretty rudimentary at the moment, so we should probably integrate that with this issue :)