Initializes positioning on this element. If a desired position is not passed,
it will make the the element positioned relative IF it is not already positioned.
@param {String} [pos] Positioning to use "relative", "absolute" or "fixed"
@param {Number} [zIndex] The zIndex to apply
@param {Number} [x] Set the page X position
@param {Number} [y] Set the page Y position
function(pos, zIndex, x, y) {
            var me = this;

            if (!pos && me.isStyle(POSITION, STATIC)) {
                me.setStyle(POSITION, RELATIVE);
            } else if (pos) {
                me.setStyle(POSITION, pos);
            }
            if (zIndex) {
                me.setStyle(ZINDEX, zIndex);
            }
            if (x || y) {
                me.setXY([x || false, y || false]);
            }
        }