`get_publicdata()` & `get_measure()`: throw meaningful error when banned due to exceedance of limits

[dimfalk]

netatmo.weather/R/get_publicdata.R

Lines 120 to 130 in c0c351a

	if (n > 500) {
	input <- menu(c("Yes", "No"),
	title = "You are about to exceed your hourly limit of 500 requests (and risking to be temporarily banned from the API).
	Do you really want to continue?")
	if (input == 2) {
	"Current request aborted by the user." |> stop()
	}
	}

[dimfalk]

cumulative exceedance is not tracked at all yet, so only empty JSON objects are returned at some point after 500 consecutive requests.