Last image not loading when previous & next buttons transition is animated

[jeremangnr]

After downloading the zipball and running the example, i felt it would be better-looking to have animation too when pressing next and previous buttons, so i went into ´(void)next´ and {(void)previous´ and set the animated flag to ´YES´ on the ´gotoImageByIndex´ call.

If you then load the local images demo and START moving with the next button until the end, you'll notice that the last image is not loaded. I fixed this by removing the ´if( !animated )´ check on ´gotoImageByIndex´, but maybe it breaks something else, haven't checked yet.

Thanks for the great work!