Resolved Handlebars escaping issue with ampersands.

This: "&lt;&amp;&gt; <b>This is bold</b> &&&"
was being rendered as: "<&> <b>This is bold</b> &&&".

Matches fix made in handlebars proper, see
https://github.com/wycats/handlebars.js/commit/bd9a84a0b7
Fixes a bug in ContentValueSupport where _old_contentValueKeys, if it were a string, would not be removed.
Fix caching issue with SC.routes.informLocation.

Since location and informLocation really just represent a single property,
they both need to update the cached value for the opposite property.
Cleans per jshint.
Corrects the RunLoop documentation.
Removes some internal classes from the docs.
Clean ups and starting run loops for unit tests.
Merge pull request #900 from FernCreek/patch/fairbanksg/handlebars-escaping

Resolved Handlebars escaping issue with ampersands.
Fix issue with sending statechart events while state transitioning.

sendEvent had a typo which allowed events to be sent while in the middle of
a state transition. Fixing that revealed that now events sent during state
transitions would be queued but never sent (at least until another event
was sent).
Changes the theme class for SC.EmptyTheme from 'sc-empty' to 'sc-empty-theme'. This fixes the conflict with 'sc-empty' used by SC.ProgressViews that causes all progress views in apps using the empty theme to not have an inner border. This is a potentially conflicting change, but less dangerous than changing the class used by SC.ProgressView, because SC.EmptyTheme doesn't have any styles. Fixes #936
Removes the necessity to trigger run loops while the scroll decelerates and only triggers the run loop when actually doing an update. This also removes an invoke warning if the first time the deceleration code runs (not within run loop) and doesn't have any velocity and so updates immediately.
Fine tunes the content view observers in SC.ScrollView. This prevents additional observers from being added to views that don't support calculatedHeight or calculatedWidth and prevents additional frame observers for being added to collection views, which reduces the duplicate calls to SC.ScrollView's contentViewFrameDidChange.
Reapplies the CSS transforms when touch scroll view's content frame changes. Because the CSS transforms are applied directly to the content view, if the content view's layout style changes, the transforms will be erased. Fixes #949.
Fixes the code to show an insertion point for SC.GridView using @nicolasbadia's code. Adds a default style for SC.GridView's default insertion point that matches SC.ListView's default. Also improves the positioning of SC.ListView's insertion point so that the insertion view can specify a different height/right/width layout if wanted.
CollectionView: fix the selection on touchEnd. Previously when an item was touched two times, after the second touch it was no longer marked as selected even if it was (correctly) part of the collection's selection, its isSelected property was NO when it was supposed to be YES. Added also a test sequence for collection touch events (covers this bug too).
Fixes failing unit test.
Removes forced requirement for subclasses of SC.CollectionView to implement calculatedHeight and calculatedWidth.
Adds @2x version for menu pane. Also tells drop-shadow to "chill out" to match panel pane.
Reverts removal of forced calculatedHeight/calculatedWidth implementation in collection view subclasses.
SC.Drag refactor

SC.Drag now fire dragEnded when cancelling a drag and drop operation
using the escape key:
https://github.com/sproutcore/sproutcore/issues/513

Also fix a possible memory leak with the _cachedDropTargets property.