The sqlalchemy_exasol dialect needs to support Exasol 4.x which does not support 
the OFFSET feature. Mark test with testing.requires.offset so that they can be skipped
of in the exasol specific test suite.

function patched onto config.  nose/pytest backends now fill
in their exception class here only when loaded
- use more public seeming api to get at py.test Skipped
exception

correctly.
fixes #3406

and ``__declare_last__`` accessors where these would no longer be
called on the superclass of the declarative base.
fixes #3383

applying any topological sort to tables on SQLite.  See the
changelog for details, but we now continue to sort
tables for SQLite on DROP, prohibit the sort from considering
alter, and only warn if we encounter an unresolvable cycle, in
which case, then we forego the ordering.  use_alter as always
is used to break such a cycle.
fixes #3378

with the psycopg2 dialect in conjunction with non-ascii values
and ``native_enum=False`` would fail to decode return results properly.
This stemmed from when the PG :class:`.postgresql.ENUM` type used
to be a standalone type without a "non native" option.
fixes #3354
- corrected the assertsql comparison rule to expect a non-ascii
SQL string

is the flag that per :ticket:`2992` causes an order by or group by
an expression that's also in the columns clause to be copied by
label, even if referenced as the expression object.   The behavior
for MSSQL is now the old behavior that copies the whole expression
in by default, as MSSQL can be picky on these particularly in
GROUP BY expressions.
fixes #3338
- Add a test that includes a composed label in a GROUP BY

That is, after exhausing all rows using the fetch methods, the
DBAPI cursor is released as before and the object may be safely
discarded, but the fetch methods may continue to be called for which
they will return an end-of-result object (None for fetchone, empty list
for fetchmany and fetchall).   Only if :meth:`.ResultProxy.close`
is called explicitly will these methods raise the "result is closed"
error.
fixes #3330 fixes #3329