Fixes issue with migration edges to allow multi-population identifiers to be used
diff --git a/models/populations/org.eclipse.stem.populationmodels/src/org/eclipse/stem/populationmodels/standard/impl/PopulationModelImpl.java b/models/populations/org.eclipse.stem.populationmodels/src/org/eclipse/stem/populationmodels/standard/impl/PopulationModelImpl.java
index 173305f..7bf2330 100644
--- a/models/populations/org.eclipse.stem.populationmodels/src/org/eclipse/stem/populationmodels/standard/impl/PopulationModelImpl.java
+++ b/models/populations/org.eclipse.stem.populationmodels/src/org/eclipse/stem/populationmodels/standard/impl/PopulationModelImpl.java
@@ -663,7 +663,7 @@
 			Edge e = edges.get(i);

 			if(e instanceof MigrationEdge) {

 				MigrationEdge me = (MigrationEdge)e;

-				if(!me.getPopulationIdentifier().equals(this.getPopulationIdentifier())) continue;

+				if(!me.getPopulationIdentifier().equals(((PopulationModelLabel)label).getPopulationIdentifier())) continue;

 				

 				// Migration is FROM A TO B

 				Node source = me.getA();