WECLAPP-31713 Add PARTIAL_BILLING

Fix line ending problem in UTLTest
Fix typo

library/src/main/java/org/mustangproject/ZUGFeRD/IExportableTransaction.java

@@ -416,7 +416,7 @@ public interface IExportableTransaction  {
 	}
 
 	/**
-	 * get the ID of the prceding invoice, which is e.g. to be corrected if this is a correction
+	 * get the ID of the preceding invoice, which is e.g. to be corrected if this is a correction
 	 *
 	 * @return the ID of the document
 	 */

library/src/main/java/org/mustangproject/ZUGFeRD/model/DocumentCodeTypeConstants.java

@@ -23,4 +23,5 @@ public class DocumentCodeTypeConstants {
 	public static final String CREDITNOTE = "381";
 	public static final String DEBITNOTE = "84";
 	public static final String CORRECTEDINVOICE = "384";
+	public static final String PARTIAL_BILLING = "326";
 }