Publish to Maven

New configuration

Configure .m2/settings.xml file
Point to the new settings

cd ~/repo/maven
mvn install --settings ~/.m2/settings.xml

Generate new keys gpg --gen-key
Get the Key Id gpg2 --list-keys
Publish your key gpg2 --keyserver hkp://pool.sks-keyservers.net --send-keys YOURKEYID

Update version

Change the version in build.xml
Change the version in maven/pom.xml
ant deploy (if it was a snapshot)
ant stage (after remove -SNAPSHOT from the version name if it was a release)
Access https://oss.sonatype.org/#stagingRepositories
Close your staging repository, to automatic check if everything is ok.
After your repository is checked as ok, click on Release button.
Check Maven Central

References

Sonatype - Apache Ant Sonatype - Releasing the Deployment Sonatype - Working with PGP Signatures