Unmaintained Whisper 2 1.3

Just an update for XenForo 1.3, no significant changes.

Thanks to @estranged for reporting. Some minor bugs are now fixed.

Style is updated for XenForo 1.2.

• Removed old code from original Whisper (missing gradients)
• Updated all CSS3 code to the latest CSS3 images module spec.
• Got rid of -o- prefix since Opera now supports -webkit- prefixes and switches its core to the Webkit engine.

Update is easy: you just need to reinstall the style (all of the images left untouched).