patch4.README

Patch note for patch4.diff

Added tests for asynchat classes simple_producer & fifo, and the find_prefix_at_end function. Check behavior of a string given as a producer.  Added tests for behavior of asynchat.async_chat when given int, long, and None terminator arguments. Added usepoll attribute to TestAsynchat to allow running the asynchat tests with poll support chosen whether it's available or not (improves coverage of asyncore code).