Changed the reference of the Utils functions to the global one

[Falke-Design]

Now it is possible for the user to overwrite Utils functions. For example for sub libraries.

var oldFindLayers = L.PM.Utils.findLayers;
L.PM.Utils.findLayers = function(map){
    var layers = oldFindLayers(map);
    console.log(layers);
    return layers;
}