Add jar to classpath. (rebased onto develop)



This is the same as gh-1628 but rebased onto develop.

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Add missing jar to classpath. The jar used to be an dependency of insight. This is no longer the case since we removed the doc section.

Nothing to test check that http://hudson.openmicroscopy.org.uk/view/All/job/OMERO-merge-robotframework-stable/ is green.