Support registration of ExceptionHandlerWrappers directly from faces-config.xml or @ExceptionHandlerWrapper

It is currently painful to register exception handlers in JSF: see reference ( [http://weblogs.java.net/blog/edburns/archive/2009/09/03/dealing-gracefully-viewexpiredexception-jsf2?force=148](http://weblogs.java.net/blog/edburns/archive/2009/09/03/dealing-gracefully-viewexpiredexception-jsf2?force=148) )

I think it should be possible to register ExceptionHandlerWrappers directly from faces-config.xml

com.example.ExceptionHandlerWrapperImpl

This would eliminate the painful 2-class registration process we have now.
#### Affected Versions
[2.1 Rev a]

Start by tracing the existing two-class exception-handler registration and how faces-config.xml is processed; compare that path with the requested exception-handler-wrapper entry and @ExceptionHandlerWrapper option. Done means an ExceptionHandlerWrapper can be registered directly through either supported mechanism and the existing registration behavior remains intact.

Written by the indexing model from the issue text.