function mixin (myClass, mixins)
{
    if (!mixins)
    {
        return;
    }

    if (!Array.isArray(mixins))
    {
        mixins = [ mixins ];
    }

    for (var i = 0; i < mixins.length; i++)
    {
        extend(myClass, mixins[i].prototype || mixins[i]);
    }
}
Applies the given `mixins` to the prototype of `myClass`.

@function mixin
@ignore
@param {Object} myClass The constructor object to mix into.
@param {Object|Array<Object>} mixins The mixins to apply to the constructor.