Update py-wtforms to 2.0.1.

Version 2.0.1
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Released July 1, 2014

- Update wheel install to conditionally install ordereddict for python 2.6.
- Doc improvements

Version 2.0
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Released May 20, 2014

- Add new `class Meta` paradigm for much more powerful customization
  of WTForms.
- Move i18n into core. Deprecate `wtforms.ext.i18n`.
- Move CSRF into core. Deprecate `wtforms.ext.csrf`.
- Fix issue rendering SelectFields with ``value=True``
- Make `DecimalField` able to use babel locale-based number formatting.
- Drop Python 3.2 support (Python3 support for 3.3+ only)
- passing ``attr=False`` to WTForms widgets causes the value to be ignored.
- `Unique` validator in `wtforms.ext.sqlalchemy` has been removed.

(kleink)