Cleaned up outdated documentation in reStructuredText and removed import checks, since we can now rely on the dependency declaration in our setup.py.

Removed no longer maintained ``configure, make, make install`` related installation files. Zope2 can only be installed via its setup.py.

  CMF trunk (2.2) no longer depends on it and older CMF versions don't run with Zope trunk

- fixed the issue shown by test_filepath (changed the initial function __name__ to 'script')
- adjusted test__name__

- made instance scripts more suitable for egg based installs

- LP #397861: exporting $PYTHON in generated 'zopectl' for fixing import issue
  with "bin/zopectl adduser"

Revert r101557 and put back version pins for zodbcode and zope.app.interface. These are actual dependencies of zope.app.zcmlfiles, which in turn is a test dependency of numerous packages we use. Having a consistent known set of packages for tests is as important as having one for production.

- removed special PluginIndexes handling in Product initialization code

- added more XXX comments to the regression tests (don't know how to run and fix them)