wx.InitAllImageHandlers has been a NOP for a long time, and is now deprecated.
wx.PySimpleApp is deprecated, wx.App(redirect=False) is exactly the same as wx.PySimpleApp.
wx 2.9 requires that all pushed EvtHandlers be popped before a window is destroyed.
Also pop evthandlers in destroy_control
Revert "BUG: Do not rely on an exception message. Look at the CTrait itself to determine if the exception came from an Event trait or not."

This reverts commit 6954ff0130e6d3fb800f4c20454f96328ecceb37.
ENH: Make a note of why parsing the exception message is necessary.
ENH: Test the fixed bug.
Patch for list_editor in qt4
Replaced the sending of an int as a mean to identify the sender by directly using the sender by providing the mapped signal with [QtCore.QObject] (QtGui.QWidget does not seem to work).
Ignore drags if can't get local instance data.
Handle drag and drop on trees with hidden roots more gracefully.
Fix issue with inserts not working correctly due to incorrect calculations.
General fix-up of drag-and-drop logic.
Fix missing self in restore method.
Formatting of code.
Remove tab character, unnecessary whitespace.
Fix `if...elif...else` chain.
Merge pull request #126 from enthought/fix/qt4-tree-editor-drop

Qt4 TreeEditor Drag and Drop Improvements
Fix PyMimeData coerce method to inspect lists for PyMimeData instances, tracking pickle status.

Also on failure of pickling, try to return a non-picklable PyMimeData.
Warn if can't pickle; handle PyMimeData subclass coercion better.
Start of some tests for qt4 clipboard.