Exceptions not handled elegantly

[andrew-pickin-epi]

eg:

Error: Error while sending response: 'com.epimorphics.lda.exceptions.VelocityRenderingException'

Warn: Invocation of method 'filterRemovalLinks' in  class com.epimorphics.lda.renderers.common.Page threw exception java.lang.NullPointerException at partials/view-links.vm[line 10, column 33] (org.apache.velocity.exception.MethodInvocationException: Invocation of method 'filterRemovalLinks' in  class com.epimorphics.lda.renderers.common.Page threw exception java.lang.NullPointerException at partials/view-links.vm[line 10, column 33])

org.apache.velocity.exception.MethodInvocationException: Invocation of method 'filterRemovalLinks' in  class com.epimorphics.lda.renderers.common.Page threw exception java.lang.NullPointerException at partials/view-links.vm[line 10, column 33]

[andrew-pickin-epi]

Part of: https://github.com/epimorphics/hmlr-ansible-deployment/issues/93