[2.7] bpo-33856: Add "help" to the welcome message of IDLE (GH-7755) (GH-7758)

Make it the same as when one runs 'python'..
(cherry picked from commit 9d49f85064c388e2dddb9f8cb4ae1f486bc8d357)

Co-authored-by: Stéphane Wirtel <stephane@wirtel.be>
2 files changed