Release of a maven module to central

This is mostly a 4.0+ concern but we'll add some notes at this stage.

We deploy to the sonatype repository which eventually puts stuff in maven central.

Read the instructions at http://central.sonatype.org/pages/apache-maven.html

1. Commit all your changes
   You're presumably working on a SNAPSHOT version - commit anything that's outstanding.
   Before doing so make sure the project pom.xml corresponds t all the rquirements. bw-util, bw-webdav are a couple of examples.
2. Execute this:
   mvn release:clean release:prepare
3. Then - assuming that works
   

   mvn release:perform

4. All sorts of activity ensues. Assuming a success message:
5. Head over to https://oss.sonatype.org and log in.
6. Click on "Staging repositories" and find the orgbedework entry
7. Click on "close" - the uploaded repository will be validated
8. If it fails - delete it and fix your source and repeat from the release step above.
   To see what failed click on the activities tab and open up the close activity. Click on the failed action and some details will be shown on the right, e.g. no description in pom.
9. If it succeds then click on "promote"