• Removed live() and added lives_and() after an excellent
  suggestion from Aristotle
  
• Default name for throws_ok now has better output when passed
  exceptions that overload "".
  
• Refectored t/Exception.t a bit
  
• Now handles bad exception classes that overload "" without
  overloading eq (thanks to Mark Fowler for bug report & patch).
  
• extended _exception_as_string to cover undef and normal exit
  
• made format of exception display in throws_ok constant with
  other functions.
  
• extended _exception_as_string to add appropriate prefix