Tweaks on pull request https://github.com/KentBeck/junit/pull/613

I have based this pull request on https://github.com/KentBeck/junit/pull/613 so it includes all those changes too.

I will probably have more tweaks, I need to check out some more stuff with dry-run releases.

@Tibor17
@dsaff 
@marcphilipp 

So far maven-release-plugin is looking good though:

    $ mvn -DdryRun=true release:prepare 
    [INFO] Scanning for projects...
    [INFO]                                                                         
    [INFO] ------------------------------------------------------------------------
    [INFO] Building JUnit 4.12-SNAPSHOT
    [INFO] ------------------------------------------------------------------------
    [INFO] 
    [INFO] --- maven-release-plugin:2.3.2:prepare (default-cli) @ junit ---
    [INFO] Verifying that there are no local modifications...
    [INFO]   ignoring changes on: **/pom.xml.backup, **/release.properties, **/pom.xml.branch, **/pom.xml.next, **/pom.xml.releaseBackup, **/pom.xml.tag
    [INFO] Executing: /bin/sh -c cd /Users/stephenc/github/junit && git status
    [INFO] Working directory: /Users/stephenc/github/junit
    [INFO] Checking dependencies and plugins for snapshots ...
    What is the release version for "JUnit"? (junit:junit) 4.12: : 
    What is SCM release tag or label for "JUnit"? (junit:junit) r4.12: : 
    What is the new development version for "JUnit"? (junit:junit) 4.13-SNAPSHOT: : 
    [INFO] Transforming 'JUnit'...
    [INFO] Not generating release POMs
    [INFO] Executing preparation goals - since this is simulation mode it is running against the original project, not the rewritten ones
    [INFO] Executing goals 'clean verify'...

...

    [INFO] Full run would be commit 1 files with message: '[maven-release-plugin] prepare release r4.12'
    [INFO] Full run would be tagging working copy /Users/stephenc/github/junit with label: 'r4.12'
    [INFO] Transforming 'JUnit'...
    [INFO] Not removing release POMs
    [INFO] Executing completion goals - since this is simulation mode it is running against the original project, not the rewritten ones
    [INFO] Full run would be commit 1 files with message: '[maven-release-plugin] prepare for next development iteration'
    [INFO] Release preparation simulation complete.
    [INFO] ------------------------------------------------------------------------
    [INFO] BUILD SUCCESS
    [INFO] ------------------------------------------------------------------------
    [INFO] Total time: 46.375s
    [INFO] Finished at: Thu Jan 17 10:15:30 GMT 2013
    [INFO] Final Memory: 7M/81M
    [INFO] ------------------------------------------------------------------------