Automatically set the SVN URL and PATH for subversion repositories

Customers need to set their SVN URL to be the repository root and the PATH when defining their repository and if they get this wrong we give an error message like "Repository URL blah does not match URL returned from repository: REPOSITORY ROOT". (NOTE this is only if they test the repo. In many cases they may not test te URL).

If we can determine the Repository root, then we should set this as the SVN URL and the path as everything else for the customers.