animate progressview with css transitions
Speeds up access to isIndeterminate in SC.ProgressView's render delegate.  Also prevents running animation from being applied to non indeterminate progress views on initial render.
Adds tests illustrating that changing orderBy on an SC.ArrayController isn't invalidating lastObject.  The test currently also fails for firstSelectableObject, because firstObject is not invalidated either.
Fixes SC.ArrayController so that when orderBy changes, the firstObject and lastObject properties are invalidated and thus recomputed if needed.
Removes old debugging console messages and makes deprecation warnings visible in debug mode only, use SC.warn and to begin with the same prefix: "Developer Warning:"
Cleans compare.js as per jslint and removes two useless tests, one of which causes Safari to stop if the inspector isn't open, because console.error() is called.
Removes invalid tests that cause Unit Tests to fail.
Fixes failing unit tests related to SC.imageQueue, which needs to execute in the context of a RunLoop and which tests weren't cleaning up themselves which caused problems with SC.ImageView tests if run later.
Fixes clean up of observers on SC.SegmentedView internal items which makes unit tests pass.
Recovers the media framework out of experimental, since it's been updated significantly and will be better served staying in a public spot for now.
Removes the poorly maintained TestControls app from within the project.
Updates master CHANGELOG to include 1.8.2 bug fixes.
Adds the showcase repository as a submodule.
Updates showcase submodule.
Adds unit test that shows that GridView calculates its items layout improperly, because the frame may not always be the same as the clippingFrame.
Fixes SC.GridView's calculation of its items layouts so that it is dependent on the frame, not the clippingFrame.  An example of this problem would be a fixed width GridView inside a ScrollView would reposition its items to fit the clippingFrame, even if the GridView's width was larger.  Another example of the problem occurred when rotating GridViews on an iPad that didn't reposition items properly.
Bumps showcase submodule to latest.
Changes URL to showcase submodule to be readable.
Changes URL to showcase submodule to be readable.
Tidies up the Tests app a little bit.