Fix compilation problems.

library/src/main/java/org/mustangproject/DirectDebit.java

@@ -9,12 +9,12 @@ public class DirectDebit implements IZUGFeRDTradeSettlementDebit {
 	/**
 	 * Debited account identifier (BT-91)
 	 */
-	protected final String IBAN;
+	protected String IBAN;
 
 	/**
 	 * Mandate reference identifier (BT-89)
 	 */
-	protected final String mandate;
+	protected String mandate;
 
 	/**
 	 * bean constructor
@@ -42,8 +42,18 @@ public class DirectDebit implements IZUGFeRDTradeSettlementDebit {
 		return this.IBAN;
 	}
 
+	public DirectDebit setIBAN(String iBAN) {
+		this.IBAN = iBAN;
+		return this;
+	}
+
 	@Override
 	public String getMandate() {
 		return this.mandate;
 	}
+
+	public DirectDebit setMandate(String mandate) {
+		this.mandate = mandate;
+		return this;
+	}
 }

library/src/main/java/org/mustangproject/FileAttachment.java

@@ -21,7 +21,7 @@ public class FileAttachment {
 		this.mimetype = mimetype;
 		this.relation = relation;
 		this.data = data;
-		description = "Additional file attachment";
+		this.description = "Additional file attachment";
 	}
 
 	public String getDescription() {
@@ -68,8 +68,4 @@ public class FileAttachment {
 		this.data = data;
 		return this;
 	}
-
-
-
-
 }

library/src/main/java/org/mustangproject/IncludedNote.java

@@ -59,10 +59,20 @@ public class IncludedNote {
     return content;
   }
 
+  public IncludedNote setContent(String content) {
+    this.content = content;
+    return this;
+}
+
   public SubjectCode getSubjectCode() {
     return subjectCode;
   }
 
+  public IncludedNote setSubjectCode(SubjectCode subjectCode) {
+    this.subjectCode = subjectCode;
+    return this;
+  }
+
   public String toCiiXml(){
     String result = INCLUDE_START + CONTENT_START +
         XMLTools.encodeXML(getContent() )+ CONTENT_END;