Python.el: Update commentary on RET-behavior

Commentary reflect that `electric-indent-mode' in enabled by default.
ChangeLog fix (do not merge to master)
Fix bug #19211 with move-end-of-line in non-interactive session.

 lisp/simple.el (line-move): If noninteractive, call line-move-1, not
 forward-line, since the former is compatible with line-move-visual
 both in terms of the column to which it moves and the return
 value.
* lisp/progmodes/prog-mode.el (prettify-symbols--compose-symbol): Refine.

Fix handling of symbols with different syntax at beginning/end or with
symbol rather than word syntax.
* lisp/gnus/gnus-cloud.el (gnus-cloud): Add :version tag.
VC API simplification: remove ability to set initial revision.

This hasn't made any sense since RCS, and was a dumb stunt then.

* vc/vc.el and all backends: API simplification; init-revision is
gone, and vc-registered functions no longer take an initial-revision
argument.
Argument removal inadvertently omitted from my previous commit.
Auto-commit of loaddefs files.
Renove duplicate code.
API simplification: remove vc-workfile-unchanged-p from pubic methods.

* vc/vc.el, vc-hooks.el, and all backends: API simplification;
vc-workfile-unchanged-p is no longer a public method (but the RCS and
SCCS back ends retain it as a private method used in state
computation). This method was redundant with vc-state and usually
implemented as a trivial call to same. Fixes the failure mode
described in bug#694.
The vc-mistrust-permissions configuration variable is gone.

* vc/vc-cvs.el, vc/vc-hooks.el, vc/vc-rcs.el, vc/vc-sccs.el: Eliminate
vc-mistrust-permissions.  It was only relevant to the RCS and SCCS
back ends and defaulted to t. Code now always mistrusts permissions -
by actual measurement the effect on performance is negligible. As a
side effect bug#11490 is now irrelevant.
Remove vc-state-heuristic from the set of public methods.

* vc/vc.el, vc-hooks.el, and all backends: API simplification;
vc-state-heuristic is no longer a public method, having been removed
where it is redundant, unnecessary, or known buggy. This eliminated
all backends except CVS.  Eliminates bug#7850.
New macro `define-inline'.

* lisp/emacs-lisp/inline.el: New file.
Remove stay-local support in svn back end, because...

...status -v is so slow that it's unusable.
Confine vc-stay-local to CVS, because it was unusable in SVN.
Finish vc-stay-local containment.

* vc/vc.el, vc-hooks.el, and all backends: API simplification;
vc-stay-local-p and repository-hostname are no longer public
methods. Only the CVS and SVN backends used these, and the SVN
support was conditioned out because svn status -v is too slow.
The CVS back end retaiin this machibery and the vc-stay-local
configuration variable now only affects it.
Update some documentation changes and todo items.
Small but crucial change for new VC registration API.
Minor eww point placement fixup

* net/eww.el (eww): Leave point in a place that doesn't cause
scrolling when displaying "Loading...".
* .gitignore: Ignore loaddefs directly under lisp, and in sub-sub-directories