Add test for upward traversal

if one tries to embed Zope within C/C++.

Made a small fix to _setDB in Mount.py to pass 
through new args passed to it.

With these changes, Zope now runs again.

- Reformat code, add docstrings, unobfuscate local var names
- Eliminate use of hasattr and simplify where possible
- Add comments
- Improve test coverage

  until a bucket is garbage collected (which may be much later than the
  expiration of that bucket), we "finalize" a bucket as soon as possible
  after it gets expired.  This effectively means that the "delete notifier"
  will be called much closer to the time that a transient object actually
  expires.
                                                                                
- Add a "_last_finalized_timeslice" counter; this counter keeps track of 
  the bucket which was finalized last.  Set the initial value of
  "_last_finalized_timeslice" to -period; this services the unit tests for
  finalization, where there can actually be a timeslice that is 0 and we 
   need to finalize that bucket.
                                                                                
- Add a series of locks to prevent finalization, replentishment, and
  garbage collection from being attempted by more than one thread
  simultaneously.
                                                                                
- Add "Fake" module for interactive testing purposes (swap out BTree for
  simpler object during stress tests for isolation purposes).
                                                                                
- Allow DATA_CLASS to be specified (this is the main data structure
  class).

- Update docs and tests to account for new finalization strategy.

data from the alpha 2 tag. Sigh.

     - Collector #1213: Fixed wrong labels of cache parameters 

     - Collector #1265: Fixed handling of orphans in ZTUtil.Batch

       sections raises an exception. 

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     - Collector #1293: Added default ports for http-server, ftp-server
       and webdav-server.

- refactored slightly
- logged when object cannot be resolved on re-indexing of an index
- made manage_reindexIndex more efficient.

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won't fail.

Collector 789:  Zope's transaction behavior flawed.
                                                                                
Historically, errors that made it up to the publisher have run outside the
context of a transaction.  This has caused problems for applications which
expect to be able to write to the database (if only temporarily, before
transaction.abort() is eventually called).
                                                                                
With this patch, we allow the error to execute in the same transaction as
the "main" request, and abort only after the error has executed.