extended possibilities to edit transaction

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

core/src/main/java/de/srsoftware/umbrella/core/model/Transaction.java

@@ -42,6 +42,12 @@ public class Transaction implements Mappable {
 		return amount;
 	}
 
+	public Transaction amount(double newVal){
+		amount = newVal;
+		dirtyFields.add(Field.AMOUNT);
+		return this;
+	}
+
 	public Transaction clearDirtyState(){
 		dirtyFields.clear();
 		return this;
@@ -65,6 +71,12 @@ public class Transaction implements Mappable {
 		return destination;
 	}
 
+	public Transaction destination(IdOrString newVal){
+		destination = newVal;
+		dirtyFields.add(Field.DESTINATION);
+		return this;
+	}
+
 	public long id(){
 		return id;
 	}
@@ -99,6 +111,12 @@ public class Transaction implements Mappable {
 		return source;
 	}
 
+	public Transaction source(IdOrString newVal){
+		source = newVal;
+		dirtyFields.add(Field.SOURCE);
+		return this;
+	}
+
 	public Set<String> tags(){
 		return tags;
 	}