* Set image dimensions based on thumbnailDimensions, to improve the transition hwil image loads
* Call scroll handler directly, instead of scroll(), so doesn't fire other handlers unintentionally
* Major refactor of how post items are added, to improve load time and perceived load time
** Adds items in chunks
** Adds items using setTimeout(func, 0), so doesn't prevent rest of UI from rendering
** Replaced item.hide()/item.fadeIn() with snappier add/removeClass()
** Ensures comments are placed in chronological order, not just array order
* Fix incorrect addItem order
* Load images after the first chunk, on first update, so see content right away
* Reduce image fadein time to 0.3s
* Make image alt attribute empty - is redundant text, and sometimes is visible while image is loading
* Image loading performance updates
** On scroll, use debounce instead of throttle, so only loads images when done scrolling - dramatically improves scroll speed
** Exit loop that load images, once it reaches the first invisible item
* On first update, temporarily stop polling, and resume again once addItems is complete -- ensures to pick up new updates that occur while loading post items
* Make sure to unbind events when clearing tag filter - otherwise doesn't rebuild posts correctly

* Added explicit hidePauseButton and showPauseButton functions
* Fix IE6 CSS layout issue
* Cleanup and comments