Edit trait

Related to <a href="https://ebi-forecast.igb.illinois.edu/redmine/issues/2198">#2198</a> and <a href = "https://ebi-forecast.igb.illinois.edu/redmine/issues/2351">#2351</a>
 We don't need to set @citation unless we have an exception and are
thus re-rendering the edit template.  So it might be cleaner to put
this line in the rescue block.