Optimization for TextPane:  only notify the TextPaneCharacterListener once per
bulk operation (like a cut or paste) instead of once per node that changes.
This is nice for auxiliary processing (like syntax colorizing) that really
only needs to know the whole range that has been affected.  And there should
be no downside to the change (since the skins use the lower-level interfaces
anyway, which are not affected).

This is a merge of revision 1525982 from trunk to branches/2.0.x.


git-svn-id: https://svn.apache.org/repos/asf/pivot/branches/2.0.x@1525983 13f79535-47bb-0310-9956-ffa450edef68