#326539 by JohnAlbin, sun, cha0s, ultimateboy, Rob Loach, Damien Tournoud: Convert 'class' attribute to use an array, not a string.

#517814 by jmstacey, justinrandell, pwolanin, drewish, Jody Lynn, aaron, dopry, and c960657: Converted File API to stream wrappers, for enhanced private/public file handling, and the ability to reference other storage mechanisms such as s3:// and flicker://.

#371374 by quicksketch, drewish, eojthebrave, and dopry: ImageCache UI in core. Hell yeah! :D Resizable, scalable, croppable, grey-scalable, rotatey images for all.