AbstractUIDetails: use identifier in getTitle

If there is a unique identifier string for the object (i.e., it
implements the Identifiable interface), and none of the more
friendly options are set (i.e.: no label, no menu leaf, no name),
then let's use the identifier over the raw class name.

Author: ctrueden

src/main/java/org/scijava/AbstractUIDetails.java

@@ -103,6 +103,11 @@ public String getTitle() {
 		// use object name, if available
 		if (getName() != null && !getName().isEmpty()) return getName();
 
+		// use the unique identifier, if available
+		if (this instanceof Identifiable) {
+			return ((Identifiable) this).getIdentifier();
+		}
+
 		// use class name as a last resort
 		return getClass().getSimpleName();
 	}