Fixed issue in SQL math negation operator where the type of the
expression would no longer be the numeric type of the original.
This would cause issues where the type determined result set
behaviors.

Change-Id: If0e339614a3686e251235fc94b6f59310c4630a5
Fixes: #3735

Fixed bug whereby the ``__getstate__`` / ``__setstate__``
methods for sqlalchemy.util.Properties were
non-working due to the transition in the 1.0 series to ``__slots__``.
The issue potentially impacted some third-party applications.
Pull request courtesy Pieter Mulder.

Fixes: #3728
Change-Id: I01ebd425bbfe145747fea2edd0d2d412c74fd84d
Pull-request: https://github.com/zzzeek/sqlalchemy/pull/286
(cherry picked from commit cab57e9bab04fbdea44690c08dff379a29eaab32)

Made a slight behavioral change in the ``sqlalchemy.ext.compiler``
extension, whereby the existing compilation schemes for an established
construct would be removed if that construct was itself didn't already
have its own dedicated ``__visit_name__``.  This was a
rare occurrence in 1.0, however in 1.1 :class:`.postgresql.ARRAY`
subclasses :class:`.sqltypes.ARRAY` and has this behavior.
As a result, setting up a compilation handler for another dialect
such as SQLite would render the main :class:`.postgresql.ARRAY`
object no longer compilable.

Fixes: #3732
Change-Id: If2c1ada4eeb09157885888e41f529173902f2b49

The processing performed by the :class:`.Boolean` datatype for backends
that only feature integer types has been made consistent between the
pure Python and C-extension versions, in that the C-extension version
will accept any integer value from the database as a boolean, not just
zero and one; additionally, non-boolean integer values being sent to
the database are coerced to exactly zero or one, instead of being
passed as the original integer value.

Change-Id: I01e647547fd7047bd549dd70e1fa202c51e8328b
Fixes: #3730

Dialed back the "order the primary key columns per auto-increment"
described in :ref:`change_mysql_3216` a bit, so that if the
:class:`.PrimaryKeyConstraint` is explicitly defined, the order
of columns is maintained exactly, allowing control of this behavior
when necessary.

Change-Id: I9e7902c57a96c15968a6abf53e319acf15680da0
Fixes: #3726

Rolled back the validation rules a bit in :class:`.Enum` to allow
unknown string values to pass through, unless the flag
``validate_string=True`` is passed to the Enum; any other kind of object is
still of course rejected.  While the immediate use
is to allow comparisons to enums with LIKE, the fact that this
use exists indicates there may be more unknown-string-comparsion use
cases than we expected, which hints that perhaps there are some
unknown string-INSERT cases too.

Change-Id: I7d1d79b374a7d47966d410998f77cd19294ab7b0
Fixes: #3725

Change-Id: I8815a68dcf6e5d27f3f82b02f939f72d9a412337

Allows custom dialects to add keywords after the
CREATE TABLE section.

Change-Id: I6fa66dfcf00ef95122f491a9115410df2746cf88