function range (length)
{
    var list = [];
    for (var i = 0; i < length; i++) list.push(i);
    return list;
}

function createFromArray (array, indices)
{
    var result = [];
    for (var i = 0; i < indices.length; i++) result.push(array[indices[i]]);
    return result;
}

function chooseRandomly (array, howMany)
{
    if (typeof(howMany) == 'undefined') howMany = 1;

    var remainingIndices = range(array.length);
    var selectedIndices = [];

    for (; howMany; howMany--)
    {
        selectedIndices = selectedIndices.concat(
            remainingIndices.splice(
                Math.floor(Math.random() * remainingIndices.length), 1));
    }

    return createFromArray(array, selectedIndices);
}

var mainBackgroundImageUrls = [

    'resources/images/nestle-background-07.jpg',
    'resources/images/nestle-background-08.jpg',
    'resources/images/nestle-background-09.jpg',
    'resources/images/nestle-background-10.jpg',
    'resources/images/nestle-background-11.jpg',
    'resources/images/nestle-background-12.jpg',
    'resources/images/nestle-background-13.jpg',
    'resources/images/nestle-background-14.jpg',
    'resources/images/nestle-background-15.jpg',
    'resources/images/nestle-background-16.jpg',
    'resources/images/nestle-background-17.jpg'
	
	];