Prevent null pointer exceptions in AbstractSearch
Always choose a valid i18n title for authority confidence icon

Prevents org.dspace.app.xmlui.cocoon.DSpaceI18NTransformer @ Translation not found for attribute title in element <img>
Merge pull request #405 from datadryad/trello-44-logging

Preventing noise in logs from cocoon.handled and DSpaceI18NTransformer