closes #172, fixes zero rated products, added some lines to the test of the XRechnung, have the XRechnung test actually wriote to file and have the XR test file validated automatically

validator/src/test/java/org/mustangproject/validator/LibraryTest.java

@@ -135,4 +135,28 @@ public class LibraryTest extends ResourceCase {
 		assertThat(res).valueByXPath("/validation/summary/@status")
 				.isEqualTo("valid");
 	}
+	/**
+	 * automatically test the xrechnung
+	 */
+	public void testXRValidation() {
+		File tempFile = new File("../library/target/testout-XR.xml");
+		ZUGFeRDValidator zfv = new ZUGFeRDValidator();
+
+		String res = zfv.validate(tempFile.getAbsolutePath());
+
+		assertThat(res).valueByXPath("count(//error)")
+				.asInt()
+				.isEqualTo(0);
+
+		assertThat(res).valueByXPath("count(//notice)")
+				.asInt()
+				.isEqualTo(0);
+		assertThat(res).valueByXPath("/validation/summary/@status")
+				.asString()
+				.isEqualTo("valid");// expect to be valid because XR notices are, well, only notices
+		assertThat(res).valueByXPath("/validation/xml/summary/@status")
+				.asString()
+				.isEqualTo("valid");
+
+	}
 }