Update alembic to 0.9.2

[pyup-bot]

There's a new version of alembic available.
You are currently using 0.9.1. I have updated it to 0.9.2

These links might come in handy: PyPI | Changelog | Repo | Docs

Changelog

0.9.2

:released: May 18, 2017

.. change:: 429
:tags: bug, mssql
🎟️ 429

 Repaired :meth:`.Operations.rename_table` for SQL Server when the
 target table is in a remote schema, the schema name is omitted from
 the "new name" argument.

.. change:: 425
:tags: feature, commands
🎟️ 425

 Added a new configuration option ``timezone``, a string timezone name
 that will be applied to the create date timestamp rendered
 inside the revision file as made availble to the ``file_template`` used
 to generate the revision filename.  Note this change adds the
 ``python-dateutil`` package as a dependency.

.. change:: 421
:tags: bug, autogenerate
🎟️ 421

 The autogenerate compare scheme now takes into account the name truncation
 rules applied by SQLAlchemy's DDL compiler to the names of the
 :class:`.Index` object, when these names are dynamically truncated
 due to a too-long identifier name.   As the identifier truncation is
 deterministic, applying the same rule to the metadata name allows
 correct comparison to the database-derived name.

.. change:: 419
:tags: bug environment
🎟️ 419

 A warning is emitted when an object that's not a
 :class:`~sqlalchemy.engine.Connection` is passed to
 :meth:`.EnvironmentContext.configure`.  For the case of a
 :class:`~sqlalchemy.engine.Engine` passed, the check for "in transaction"
 introduced in version 0.9.0 has been relaxed to work in the case of an
 attribute error, as some users appear to be passing an
 :class:`~sqlalchemy.engine.Engine` and not a
 :class:`~sqlalchemy.engine.Connection`.

.. changelog::

Got merge conflicts? Close this PR and delete the branch. I'll create a new PR for you.

Happy merging! 🤖

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