Move Build Definition Template guide to Administrator's Guides

http://continuum.apache.org/docs/1.1/user_guides/managing_builddef/builddefTemplate.html refers to defining build templates.

As it is under the "User Guide" section of the web-site, this implies that it is available to ordinary users.

However, this does not seem to be the case on vmbuild.apache.org - there is no "Build Definitions Templates" menu item as far as I can see.

This probably means that it is an Admin task - in which case the documentation should be moved to the appropriate section.