Zope.session

==================

- Add an explicit `provides` to the IClientId adapter declaration in
adapter.zcml.

- Add option to disable implicit sweeps in
PersistentSessionDataContainer.

==================

- Add test extra to declare test dependency on ``zope.testing``.

- Use Python's ``doctest`` module instead of depreacted
``zope.testing.doctest``.

==================

- Fix Python 2.4 hmac compatibility issue by only using hashlib in
Python versions 2.5 and above.

- Use the CookieClientIdManager's secret as the hmac key instead of the
message when constructing and verifying client ids.

- Make it possible to construct CookieClientIdManager passing cookie namespace
and/or secret as constructor's arguments.

- Use zope.schema.fieldproperty.FieldProperty for "namespace" attribute of
CookieClientIdManager, just like for other attributes in its interface.
Also, make ICookieClientIdManager's "namespace" field an ASCIILine, so
it accepts only non-unicode strings for cookie names.

==================

- Restore compatibility with Python 2.4.

==================

- Don't raise deprecation warnings on Python 2.6.

- Drop dependency on ``zope.annotation``. Instead, we make classes implement
`IAttributeAnnotatable` in ZCML configuration, only if ``zope.annotation``
is available. If your code relies on annotatable `CookieClientIdManager`
and `PersistentSessionDataContainer` and you don't include the zcml classes
configuration of this package, you'll need to use `classImplements` function
from ``zope.interface`` to make those classes implement `IAttributeAnnotatable`
again.

- Drop dependency on zope.app.http, use standard date formatting function
from the ``email.utils`` module.

- Zope 3 application bootstrapping code for session utilities was moved into
zope.app.appsetup package, thus drop dependency on zope.app.appsetup in this
package.

- Drop testing dependencies, as we don't need anything behind zope.testing and
previous dependencies was simply migrated from zope.app.session before.

- Remove zpkg files and zcml slugs.

- Update package's description a bit.

==================

- Add an ability to set cookie effective domain for CookieClientIdManager.
This is useful for simple cases when you have your application set up on
one domain and you want your identification cookie be active for subdomains.

- Python 2.6 compatibility change. Encode strings before calling hmac.new()
as the function no longer accepts the unicode() type.