Replaces a wide array of Sphinx-relative doc references
with an abbreviated absolute form now supported by
zzzeeksphinx.

Change-Id: I94bffcc3f37885ffdde6238767224296339698a2

zzzeeksphinx 1.1.2 in git can now convert short
prefix names in a configured lookup to fully qualified module
names, so that
we can have succinct and portable pyrefs
that still resolve absolutely.
It also includes a formatter that will format all pyrefs
in a fully consistent way regardless of the package path,
by unconditionally removing all package tokens but always
leaving class names in place including for methods, which
means we no longer have to deal with tildes in pyrefs.

The most immediate goal of the absolute prefixes is
that we have lots of
"ambiguous" names that appear in muliple places, like select(),
ARRAY, ENUM etc.   With the incoming future packages there
is going to be lots of name overlap so it is necessary
that all names eventually use absolute package paths
when Sphinx receives them.

In multiple stages, pyrefs will be converted using the
zzzeeksphinx tools/fix_xrefs.py tool so that doclinks can
be made absolute using symbolic prefixes.

For this review, the actual search and replace of symbols
is not performed, instead some general cleanup to prepare
the docs as well as a lookup file used by the tool
to do the conversion.   this relatively small patch will
be backported
with appropriate changes to 1.3, 1.2, 1.1 and the tool
can then be run on each branch individually.  We are shooting
for almost no warnings at all for master (still a handful
I can't figure out which don't seem to have any impact)
, very few for 1.3,
and for 1.2 / 1.1 we hope for a significant reduction
in warnings.

Overall for all versions pyrefs should
always point to the correct target, if they are in fact
hyperlinked.  it's better for a ref to go nowhere and
be plain text than go to the wrong thing.  Right now,
hundreds of API links are pointing to the wrong thing
as they are ambiguous names such as refresh(), insert(),
update(), select(), join(), JSON etc. and Sphinx sends these all
to essesntially random destinations among as many as five
or six possible choices per symbol.  A shorthand system
that allows us to use absolute refs without having
to type out a full blown absoulte module is the only
way this is going to work, and we should ultimately
seek to abandon any use of prefix dot for lookups.  Everything
should be on an underscore token so at the very least the module
spaces can be reorganized without having to search and replace
the entire documentation every time.

Change-Id: I484a7329034af275fcdb322b62b6255dfeea9151
(cherry picked from commit d8d755ad619e2ee78f2c7cb60ae9a1feee4c6d76)
(cherry picked from commit 8f992000a4ed59d5f91796cef5cec7697ce464fc)

Change-Id: I9bc4d0ddfa93f13e6717b89fa9934f1b8052147f
(cherry picked from commit 833583458c69e24e797c300c934da0ff04348db5)

- fix a few "seealso"s
- ComparableProprerty's "superseded in 0.7" becomes deprecated in 0.7

Backport to currently maintained doc versions 1.2, 1.1

Change-Id: Ib1fcb2df8673dbe5c4ffc47f3896a60d1dfcb4b2
(cherry picked from commit 885f15a306efc4c907ca82fa13871992ee556466)

Change-Id: I6a71f4924d046cf306961c58dffccf21e9c03911
(cherry picked from commit 6f270fb0e344016ce526e0a1ecb3e3de9ffd1e3b)

Applied on top of a pure run of black -l 79 in
I7eda77fed3d8e73df84b3651fd6cfcfe858d4dc9,  this set of changes
resolves all remaining flake8 conditions for those codes
we have enabled in setup.cfg.

Included are resolutions for all remaining flake8 issues
including shadowed builtins, long lines, import order, unused
imports, duplicate imports, and docstring issues.

Change-Id: I4f72d3ba1380dd601610ff80b8fb06a2aff8b0fe

This is a straight reformat run using black as is, with no edits
applied at all.

The black run will format code consistently, however in
some cases that are prevalent in SQLAlchemy code it produces
too-long lines.   The too-long lines will be resolved in the
following commit that will resolve all remaining flake8 issues
including shadowed builtins, long lines, import order, unused
imports, duplicate imports, and docstring issues.

Change-Id: I7eda77fed3d8e73df84b3651fd6cfcfe858d4dc9

Fixed bug where the declarative scan for attributes would receive the
expression proxy delivered by a hybrid attribute at the class level, and
not the hybrid attribute itself, when receiving the descriptor via the
``@declared_attr`` callable on a subclass of an already-mapped class. This
would lead to an attribute that did not report itself as a hybrid when
viewed within :attr:`.Mapper.all_orm_descriptors`.

Fixes: #4326
Change-Id: I582d03f05c3768b3344f93e3791240e9e69b9d1e
(cherry picked from commit 626356842d77d4ec6427b3bfc04bdff93d24d246)

Added new argument :paramref:`.attributes.set_attribute.inititator`
to the :func:`.attributes.set_attribute` function, allowing an
event token received from a listener function to be propagated
to subsequent set events.

Change-Id: I6ede21e42153026ab46a1d2ec33aa3f999db98e2

Fixed 1.2 regression regarding new bulk_replace event
where a backref would fail to remove an object from the
previous owner when a bulk-assignment assigned the
object to a new owner.

As this revisits the Event tokens associated with
AttributeImpl objects, remove the verbosity of the
"inline lazy init" pattern; the Event token is a simple
slotted object and should have minimal memory overhead.

Change-Id: Id188b4026fc2f3500186548008f4db8cdf7afecc
Fixes: #4171