Backport rpc.py rev 1.28 dating from 21Jan04

Backport rpc.py rev 1.28 dating from 21Jan04

rpc.py:SocketIO - Large modules were generating large pickles when downloaded
to the execution server.  The return of the OK response from the subprocess
initialization was interfering and causing the sending socket to be not
ready.  Add an IO ready test to fix this.  Moved the polling IO ready test
into pollpacket().

Fix typo in rpc.py, s/b "pickle.PicklingError" not "pickle.UnpicklingError".

idlever.py should be 1.0.4 to align with NEWS.txt.  There was no IDLE release
at 2.3.1 which accounts for the unsync.

M NEWS.txt
M idlever.py
M rpc.py