[maven-release-plugin] prepare release maven-jarsigner-plugin-1.3.1

git-svn-id: https://svn.apache.org/repos/asf/maven/plugins/trunk@1555247 13f79535-47bb-0310-9956-ffa450edef68
[maven-release-plugin] prepare for next development iteration

git-svn-id: https://svn.apache.org/repos/asf/maven/plugins/trunk@1555249 13f79535-47bb-0310-9956-ffa450edef68