Plone.scale

------------------

Bug fixes:

- Remove unused dependency.
[gforcada]

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Bug fixes:

- Only convert JPEG to greyscale if they actually are and not when the image
has less than 256 colors. This bug was introduced in 2.1 with PR 13.
[fschulze]

- Preserve color profile in scaled images.
[fschulze]

----------------

New features:

- Choose an appropriate image mode in order to reduce file size.
[didrix]

Bug fixes:

- Require the ``six`` package so we can more easily check number types.
On Python 3 ``long`` has been merged into ``int``. [maurits]

- When getting an outdated scale, don't throw it away when there is no
factory. [maurits]

- Avoid TypeErrors when looking for outdated scales.
Fixes `issue 12 <https://github.com/plone/plone.scale/issues/12>`_.
[maurits]

- Catch KeyError when deleting non existing scale. This can happen in corner cases.
Fixes `issue 15 <https://github.com/plone/plone.scale/issues/15>`_.
[maurits]

- Set ``zip_safe=False`` in ``setup.py``. Otherwise you cannot run
the tests of the released package because the test runner does not
find any tests in the egg file. Note that this is only a problem in
zc.buildout 1.x: it uses unzip=False by default. zc.buildout 2.x no
longer has this option and always unzips eggs. [maurits]

----------------

New:

- Assume a width or height of zero is semantically the same as None already was:
Use the other dimension to scale, calculate the missing one.
[jensens, thet]

- Scaled GIFs are converted to RGBA PNG images instead of converting them to JPEG.
[thet, jensens]

Fixes:

- Don't scale images up for direction "down".
[thet]

- Major housekeeping, code refactored in order to reduce complexicty.
[jensens]

------------------

New:

- Use an adapter to lookup the actual factory for scaling.
Deprecated passing the factory as named parameter along,
because this had not enough flexibility:
If addons want to provide alternative methods to scale (i.e. cropping),
now a specific adapter can perform the work.
[jensens]

Fixes:

- Minor housekeeping.
[jensens]

------------------

Fixes:

- Fix KeyError in storage.AnnotationStorage._cleanup when attempting
to delete the storage for the same key twice.
[fulv]