[ScrollPane] javadoc on hmin hmax vmin vman need to be clarified

A confusing situation can happen, because default range [0.0 ... 1.0] of hValue and vValue (which are restricted by hmin hmax vmin vmax) is not specified.

http://stackoverflow.com/questions/14007654/how-to-set-the-desired-position-scrollpane/

So, it is needed, to specify the default values of hmin, hmax, vmin and vmax in javadoc.