Add 'extensions' directive in zope.conf

[Rodrigo Senra]

This patch adds the directive 'extensions' to zope.conf. If overriden in zope.conf, then the specified directory will be used for ExternalMethods instead of the default $INSTANCE/Extensions.

This was discussed in the zope users list under the subject 'Give 'Extensions' a configurable directory in zope.conf'.

The changes so far relative to svn truck are:

   * /lib/python/Products/ExternalMethod/help/ExternalMethod.py

     - docstring comment

   * /lib/python/Products/ExternalMethod/ExternalMethod.py

     - little typos (not related, but since I was there <wink>)
     - docstring comment

   * /etc/zope.conf

     - new directive 'extensions', comments and example

   * /lib/python/Zope/Startup/zopeschema.xml

     - new directive 'extensions' (type key)

   * /lib/python/App/Extensions.py

     - in getPath() check if directive 'extensions' is overriden in zope.conf,
       and use it instead.

[Rodrigo Senra (rsenra)]

This is supposed to be considered for Zope 2.8.

Another collector entry was filed under http://collector.zope.org/ColDev/118

If that was a mistake, and you know how to correct it please do so.
<wink>

[Tres Seaver (tseaver)]

Feature now committed on the trunk. Thanks for the patch!

[Rodrigo Senra (rsenra)]

Thank you people, glad to see the patch made it through.
cheers,
Rod Senra