[maven-release-plugin] prepare release archiva-1.3.7

git-svn-id: https://svn.apache.org/repos/asf/archiva/branches/archiva-1.3.x@1583090 13f79535-47bb-0310-9956-ffa450edef68
[maven-release-plugin] prepare for next development iteration

git-svn-id: https://svn.apache.org/repos/asf/archiva/branches/archiva-1.3.x@1583092 13f79535-47bb-0310-9956-ffa450edef68