Bug 199

At the moment an uncaught exception causes a stract trace to be printed in the console. In Java 5, it is 
relatively easy to catch those exception by setting a default exception handler by calling 
Thread.setDefaultUncaughtExceptionHandler(). We should extend the GUI such that uncaught 
exceptions are processed rather than printed to the console.

A first implementation should provide a nice dialog showing the error message, with a button to show 
more details (the stack trace). The stack trace must then be cut'n'pastable (i.e. it must be possible to 
select the text - easy if the correct control is used). This is similar to how windows deals with 
exceptions.

A second implementation should offer to email the stack trace together with an optional description of 
what the user was doing, a copy of the model, and various version information to our internal mailing 
list (or some other address).

The framework must be flexible enough such that other exceptions can be processed as well, e.g., if we 
actually catch an exception, but do not know how to process it, then we should call the default handler 
rather than simply ignore the exception.