Plone.reload

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

- Removed the manual cleanup approach for extra registries populated by ZCML
parsing. Instead we use the registry of cleanup functions inside
zope.testing.cleanup to automatically pick up all cleaning functions.
[hannosch]

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

- Wrap the setupFinalLogging method of the Zope2 starter objects to initialize
our internal modified times registry once after Zope is finished loading.
This is the closest I could find that resembles a `Zope is finished loading`
event and should help to remove the double-reload behavior.
[hannosch]

- Only expose the reload view in Zope 2 development mode.
[hannosch]

- In case of errors during ZCML reload, restore the original global site
manager state, instead of leaving it in a broken state. This allows you to
fix and retry the ZCML reload as many times as you need.
[hannosch]

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

- Merged the two distinct views into one called reload. Added a somewhat
nicer UI to it and explain some of the current limitations on that page.
[hannosch]

- Refactored ZCML loading code a bit. Always do an automatic code reload
before reloading ZCML.
[hannosch]

- Removed all blacklisting code.
[hannosch]

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

- Disabled blacklist until it can be made configurable. The speedup is hardly
noticeable anyway, and it can block too much (especially if plone.reload
is being used in a lib/python style deployment rather than as an egg).
[optilude]

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

- Merged r20 from http://bazaar.launchpad.net/~refreshng-dev/refreshng/dev.
This fixes https://bugs.launchpad.net/refreshng/+bug/175898.
[hannosch]

- Removed various levels of caching which turned out to be premature and
caused lots of modules not to be found.
[hannosch]

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

- Made the code reload available as its own code_reload view.
[hannosch]

- Integrated xreload.py from RefreshNG and added a first working version of a
general manual code reload feature.
[hannosch]