(svn_delta_edit_fns_t): new funcs `add_root' and `replace_root'.
(svn_delta_edit_fns_t): new funcs `add_root' and `replace_root'.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion