add currentValue and to to the onStop callback

sometimes on iOS it shows random values if animation is on. To correct this we need the currentValue and the endvalue (to) to adjust the value
Updated Readme, coffee source and version number according to c10511e4ea429e524ddda56cd25da31b027c7756
Date.now() does not work on IE < IE9. Fixing it.
v1.2.3 Date.now bugfix for IE < IE9