Remove code deprecated before version 1.1

Remove code deprecated before version 1.1

- Remove deprecated method ``get_primary_keys` in the :class:`.Dialect` and
  :class:`.Inspector` classes.
- Remove deprecated event ``dbapi_error`` and the method ``ConnectionEvents.dbapi_error`.
- Remove support for deprecated engine URLs of the form ``postgres://``.
- Remove deprecated dialect ``mysql+gaerdbms``.
- Remove deprecated parameter ``quoting`` from :class:`.mysql.ENUM`
  and :class:`.mysql.SET` in the ``mysql`` dialect.
- Remove deprecated function ``comparable_property``. and function
  ``comparable_using`` in the declarative extension.
- Remove deprecated function ``compile_mappers``.
- Remove deprecated method ``collection.linker``.
- Remove deprecated method ``Session.prune`` and parameter ``Session.weak_identity_map``.
  This change also removes the class ``StrongInstanceDict``.
- Remove deprecated parameter ``mapper.order_by``.
- Remove deprecated parameter ``Session._enable_transaction_accounting`.
- Remove deprecated parameter ``Session.is_modified.passive``.
- Remove deprecated class ``Binary``. Please use :class:`.LargeBinary`.
- Remove deprecated methods ``Compiled.compile``, ``ClauseElement.__and__`` and
  ``ClauseElement.__or__`` and attribute ``Over.func``.
- Remove deprecated ``FromClause.count`` method.
- Remove deprecated parameter ``Table.useexisting``.
- Remove deprecated parameters ``text.bindparams`` and ``text.typemap``.

- Remove boolean support for the ``passive`` parameter in ``get_history``.
- Remove deprecated ``adapt_operator`` in ``UserDefinedType.Comparator``.

Fixes: #4643
Change-Id: Idcd390c77bf7b0e9957907716993bdaa3f1a1763