function Message(properties) {
    if (properties)
        for (var keys = Object.keys(properties), i = 0; i < keys.length; ++i)
            this[keys[i]] = properties[keys[i]];
}
Constructs a new message instance.

This function should also be called from your custom constructors, i.e. `Message.call(this, properties)`.
@classdesc Abstract runtime message.
@constructor
@param {Object.<string,*>} [properties] Properties to set
@see {@link Class.create}