Change default port # from 9999 to 8100, to match zope.conf
(well, on Zope trunk anyway -- the ZEO client example appears
to have gone missing from zope.conf on Zope3 trunk).

 port we plan to listen on.

configuration file can be used for both the runzeo and zeoctl scripts.
This makes it easier to keep all the configuration needed to support the
ZEO server process in a single file.
For more explanation of the changes, see
http://zope.org/Members/fdrake/WikiBlog/ZEOServerConfiguration

I've fixed the various scripts etc. in the CVS so that I can now install a ZEO client/server setup. The way it actually ended up working is:

- runzope.py and zopectl.py are moved to Zope/Startup/run.py and Zope/zdaemon/zopectl.py respectively
- bin/mkzopeinstance now takes a "-z/--zeo host:port" which sets up a custom_zodb.py in the new zope instance home
- bin/mkzeoinstance now overrides less, because...
- ZEO/mkzeoinst.py generates an additional script, runzeo, which is the "runner" for the ZEO server. Both it an the zeoctl script need to know about the ZOPE_HOME, so that's been added to the scripts (via the params)
- fixed setup.py so it installed ZEO/schema.xml

 - the scripts won't be in the user's $PATH, so override that lookup
   in from mkzeoinst.py in the mkzeoinstance script
 - the scripts won't be executable, so prepend commands with $python

It may be reasonable to change this more, but the benefits aren't clear.
(These changes will be used from the new-install-branch.)

make it easier to re-locate an instance.

package.

'show' command.

it is already absolute; there may be a good reason.

Add an <eventlog> section to the runner schema.
Some comment and docstring tweakage.

types.

Add socket-name to runner conf template.
Check that the port isn't in use already.