`py-comint-output-filter-function' removed

There is no use-case for it currently
`py-comint-output-filter-function' removed

There is no use-case for it currently

`python-compilation-regexp-alist' renamed `py-compilation-regexp-alist'
`py-shell' uses new `py-shell-mode', lp:1331951

`py-shell-mode-map'

 M-x describe-mode RET mentions edit available commands
 Menu "Py-Shell"
`py-shell' uses new `py-shell-mode', lp:1331951

`py-shell-mode-map'

 M-x describe-mode RET mentions edit available commands
 Menu "Py-Shell"

As a result `py-shell-map' is removed. The derived mode could't
be called `py-shell', as this is in use already.