zoom state should be initial when zooming out to min scale

[dasmikko]

I'm currently using the widget with the following settings:

initialScale: 1.0,
minScale: 1.0,
maxScale: 3.0

I was expecting when i'm zooming out to the min scale, the zoom state should be either originalSize or initial. But it returns the state zooming

[renancaraujo]

Related to #61 and the issues pointed on #60

[renancaraujo]

That only happens when we have the same value as initialScale and minScale. The reverse can occur when initialScale and maxScale share values.
To go solve this bug we have to detect the current scale factor whenever the scaling gesture (and its animations) ends.
Working on it.