Add sha1 checksum property to PROPFIND response for files.
Add sha1 checksum property to PROPFIND response for files.

* subversion/mod_dav_svn/liveprops.c
  (props): Add SVN_PROPID_sha1_checksum.
  (insert_prop_internal): Handle SVN_PROPID_sha1_checksum.

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