Build script changes to allow packaging and deployment to Maven central using maven-ant-tasks.

Updated build.properties to contain the sonatype urls. Updated build.xml so that gpg signing works for each accompanying artifact type. Updated pom.xml to allow templated group and artifact ids.

Use 1.4 version of gpg plugin for signing Maven upload.
Merge pull request #96 from lordnelson/maven-to-9.2-branch

Build script changes to allow packaging and deployment to Maven central ...