Remove use of special RELEASE version for joda-time

[janbartel]

Using the special maven keyword of RELEASE for a dependency version means that builds are not repeatable.

[mziccard]

I'm +1 for this. I don't expect crazy updates coming from joda-time but better safe than sorry, @aozarov?

[aozarov]

Yes. @ajkannan is working on a fix.