firewalls and security proxies.

- Launchpad #374719: introducing new ZPublisher events:
  PubStart, PubSuccess, PubFailure, PubAfterTraversal and PubBeforeCommit

- Launchpad #373658: traversal using (un)restrictedTraverse 
  no longer depends no the existence of a request 

  extended the test suite.

- Launchpad #373601: abort transaction before connection close in order to
  prevent connection leaks in case of persistent changes after the main
  transaction is closed.

- Launchpad #373621: catching and logging exceptions that could cause
  leaking of worker threads

  leaking of worker threads

  ``not debug``). Also, the check for exception constructor arguments
  didn't account for exceptions that didn't override the ``__init__``
  (which are most of them). The combination of those two problems
  caused the ``standard_error_message`` not to be called. Fixes
  https://bugs.edge.launchpad.net/zope2/+bug/372632 .

ZODB >=3.0.0b1   compatiblity

o Via https://bugs.launchpad.net/zope2/+bug/367393 

o See http://www.owasp.org/index.php/HTTPOnly for a description of the
  attribute.
  
o Patch from Stephan Hofmockel via https://bugs.launchpad.net/zope2/+bug/367393 

No longer depend on `zope.app.locales`. Zope2 uses almost none of the translations provided in the package and is not required for most projects. The decision to include locales is left to the application developer now.

Removed the dependency on `zope.app.testing` in favor of providing a more minimal placeless setup as part of ZopeTestCase for our own tests.