Add support to ``FETCH {FIRST | NEXT} [ count ] {ROW | ROWS}
 {ONLY | WITH TIES}`` in the select for the supported backends,
currently PostgreSQL, Oracle and MSSQL.

Fixes: #5576
Change-Id: Ibb5871a457c0555f82b37e354e7787d15575f1f7

Fixed bug where an error was not raised for lower-case
:func:`_column` added to lower-case :func:`_table` object. This now raises
:class:`_exc.ArgumentError` which has always been the case for
upper-case :class:`_schema.Column` and :class:`_schema.Table`.

Fixes: #5618
Change-Id: Ifcbdf27c022fd2996a5b99559df71fc1c1e0f19c

Fixed bug where an UPDATE statement against a JOIN using MySQL multi-table
format would fail to include the table prefix for the target table if the
statement had no WHERE clause, as only the WHERE clause were scanned to
detect a "multi table update" at that particular point.  The target
is now also scanned if it's a JOIN to get the leftmost table as the
primary table and the additional entries as additional FROM entries.

Fixes: #5617
Change-Id: I26d74afebe06e28af28acf960258f170a1627823

Added support for reflecting "identity" columns, which are now returned
as part of the structure returned by :meth:`_reflection.Inspector.get_columns`.
When reflecting full :class:`_schema.Table` objects, identity columns will
be represented using the :class:`_schema.Identity` construct.

Fixed compilation error on oracle for sequence and identity column
``nominvalue`` and ``nomaxvalue`` options that require no space in them.

Improved test compatibility with oracle 18.

As part of the support for reflecting :class:`_schema.Identity` objects,
the method :meth:`_reflection.Inspector.get_columns` no longer returns
``mssql_identity_start`` and ``mssql_identity_increment`` as part of the
``dialect_options``. Use the information in the ``identity`` key instead.

The mssql dialect will assume that at least MSSQL 2005 is used.
There is no hard exception raised if a previous version is detected,
but operations may fail for older versions.

Fixes: #5527
Fixes: #5324
Change-Id: If039fe637c46b424499e6bac54a2cbc0dc54cb57

It's better, the majority of these changes look more readable to me.
also found some docstrings that had formatting / quoting issues.

Change-Id: I582a45fde3a5648b2f36bab96bad56881321899b

The :meth:`_sql.Join.alias` method is deprecated and will be removed in
SQLAlchemy 2.0.   An explicit select + subquery, or aliasing of the inner
tables, should be used instead.

Fixes: #5010
Change-Id: Ic913afc31f0d70b0605f9a7af2742a0de1f9ad19

As the test suite has widespread use of many patterns
that are deprecated, enable SQLALCHEMY_WARN_20 globally
for the test suite but then break the warnings filter
out into a whole list of all the individual warnings
we are looking for.  this way individual changesets
can target a specific class of warning, as many of these
warnings will indivdidually affect dozens of files
and potentially hundreds of lines of code.

Many warnings are also resolved here as this
patch started out that way.   From this point
forward there should be changesets that target a
subset of the warnings at a time.

For expediency, updates some migration 2.0 docs
for ORM as well.

Change-Id: I98b8defdf7c37b818b3824d02f7668e3f5f31c94

Several operators are renamed to achieve more consistent naming across
SQLAlchemy.

The operator changes are:

* `isnot` is now `is_not`
* `not_in_` is now `not_in`

Because these are core operators, the internal migration strategy for this
change is to support legacy terms for an extended period of time -- if not
indefinitely -- but update all documentation, tutorials, and internal usage
to the new terms.  The new terms are used to define the functions, and
the legacy terms have been deprecated into aliases of the new terms.

Fixes: #5429
Change-Id: Ia1e66e7a50ac35d3f6260d8bf6ba3ce8087cbad2