Prevent NPEs on new user creation.

EssentialsGroupManager/src/org/anjocaido/groupmanager/dataholder/WorldDataHolder.java

@@ -162,6 +162,9 @@ public class WorldDataHolder {
 		}
 		
 		// Search for a LastName match
+		
+		if (nameToUUIDLookup.containsKey(currentName)) {
+			
 			for (String uid : getUUIDLookup(currentName)) {
 				
 				User usr = getUsers().get(uid);
@@ -179,6 +182,7 @@ public class WorldDataHolder {
 				}
 				
 			}
+		}
 			
 		
 		// No user account found so create a new one.