Log Message:
Update to 0.21.1:

0.21.1 (2014-10-18)
===================

Features added
--------------

* New ``cythonize`` option ``-a`` to generate the annotated HTML source view.

* Missing C-API declarations in ``cpython.unicode`` were added.

* Passing ``language='c++'`` into cythonize() globally enables C++ mode for
  all modules that were not passed as Extension objects (i.e. only source
  files and file patterns).

* ``Py_hash_t`` is a known type (used in CPython for hash values).

* ``PySlice_*()`` C-API functions are available from the ``cpython.slice``
  module.

* Allow arrays of C++ classes.

Bugs fixed
----------

* Reference leak for non-simple Python expressions in boolean and/or expressions.

* To fix a name collision and to reflect availability on host platforms,
  standard C declarations [ clock(), time(), struct tm and tm* functions ]
  were moved from posix/time.pxd to a new libc/time.pxd.  Patch by Charles
  Blake.

* Rerunning unmodified modules in IPython's cython support failed.
  Patch by Matthias Bussonier.

* Casting C++ ``std::string`` to Python byte strings failed when
  auto-decoding was enabled.

* Fatal exceptions in global module init code could lead to crashes
  if the already created module was used later on (e.g. through a
  stale reference in sys.modules or elsewhere).

* ``cythonize.py`` script was not installed on MS-Windows.

Other changes
-------------

* Compilation no longer fails hard when unknown compilation options are
  passed.  Instead, it raises a warning and ignores them (as it did silently
  before 0.21).  This will be changed back to an error in a future release.