Feature suggestion: Logistic curve fitting

[WLenhard]

Thanks for the great tool! A possible enhancement would be to a logistic curve fitting. Exponential growth cannot go on forever, either because all are infected or the preventive measures work. The function then follows a logistic curve, just like it already does in Korea and China. The point x0, when the growth does not speed up anymore but first goes into a linear function and then takes a logarithmic curve would be extremely interessting to find, either by providing both the exponential and a logistic curve fit or a test, which of both better fit the data.

Best regards and thanks for the fantastic tool! Wolfgang