Running on Java 6

As of M28, Okapi requires Java 7. However, some legacy WorldServer installations still use Java 6.

In order to support these installations, we have a backported version of the code on the java6 branch that can be used. This requires a specially-built version of Okapi, which has itself been backported to be compatible with Java 6. A partial backport that is sufficient to support this project can be found on the dev-java-1.6 branch of the tingley/okapi fork on bitbucket. You will need to build and install this code locally with mvn clean install prior to building the java6 branch of this code. The Java 1.6 backport of Okapi will be installed under the artifact version [release]-java6, for example 0.30-java6.