Generate .sha1 and .md5 for dist files to comply with http://www.apache.org/dev/release-signing.html (.asc still to be manually generated as per http://www.apache.org/dev/release-signing.html#openpgp-ascii-detach-sig)

git-svn-id: https://svn.apache.org/repos/asf/cocoon/branches/BRANCH_2_1_X@1451136 13f79535-47bb-0310-9956-ffa450edef68
[COCOON-2334] Patch applied

git-svn-id: https://svn.apache.org/repos/asf/cocoon/branches/BRANCH_2_1_X@1451137 13f79535-47bb-0310-9956-ffa450edef68