[CherryPy] #1074: Provide an overrideable method to generate 'now' values within Session providers

[CherryPy]

#1074: Provide an overrideable method to generate 'now' values within Session
providers
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Reporter: lakin | Owner: fumanchu
Type: defect | Status: new
Priority: normal | Milestone:
Component: CherryPy code | Keywords:
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The default session provider algorithms use naive datetime instances.
Session providers may want to use utc datetimes, or tz aware datetimes
depending on their needs.

This diff refactors the session lib so that there is an method self._now()
which can be overridden by subclasses. It was made against 3.2.0, but
should probably apply cleanly to trunk.

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Ticket URL: <http://cherrypy.org/ticket/1074>
CherryPy <http://www.cherrypy.org>
CherryPy - a pythonic, object-oriented HTTP framework