Improve print all exceptions option

With this patch we'll print the exceptions up to the function that catches them (it helps us while debugging).
I've changed the output format to the format that Throwable.java uses.
I've added some tests for nested exceptions (we didn't have one!) and finally clauses.
Nit: you caught some indentation issues in this method, but there's still one more: the method body as a whole should be indented two more spaces.