Add support for the release plugin
Add support for signing a release
Specify a version for the maven gpg plugin
Use the gpg agent for signing

to work around a bug in the maven release plugin. See
http://jira.codehaus.org/browse/MRELEASE-263
Add a release repository to the pom
[maven-release-plugin] prepare release v1.0
[maven-release-plugin] prepare for next development iteration