* Reclassified most runtime-generated errors as Errors rather than Exceptions. This...

* Reclassified most runtime-generated errors as Errors rather than Exceptions.  This involved both a parent reasignment and a name change.  At this point, the only remaining Exception is UnicodeException.
* Renamed ArrayBoundsException to RangeError in an attempt to be more general.
* Renamed onArrayBoundsError callback to onRangeError to make handling of these conditions more general as well.  Ideally, this will allow the same callback to be used for other purposes in the future.

git-svn-id: http://svn.dsource.org/projects/druntime/trunk@42 4a9d5153-6564-4b3f-b5e1-7e8e9dac548f