YANG: Line number and character position addition for cardinality failure + Increase readability of Error message and function name

Change-Id: I467a536a9d2a6cbb29873491fdb0a91f211deefd
diff --git a/src/test/java/org/onosproject/yangutils/parser/impl/listeners/LeafListenerTest.java b/src/test/java/org/onosproject/yangutils/parser/impl/listeners/LeafListenerTest.java
index 39fd4d7..da9bb35 100644
--- a/src/test/java/org/onosproject/yangutils/parser/impl/listeners/LeafListenerTest.java
+++ b/src/test/java/org/onosproject/yangutils/parser/impl/listeners/LeafListenerTest.java
@@ -120,7 +120,7 @@
     @Test
     public void processLeafConfigInvalidCardinality() throws IOException, ParserException {
         thrown.expect(ParserException.class);
-        thrown.expectMessage("YANG file error: Invalid cardinality of config in leaf \"invalid-interval\".");
+        thrown.expectMessage("YANG file error: \"config\" is defined more than once in \"leaf invalid-interval\".");
         YangNode node = manager.getDataModel("src/test/resources/LeafConfigInvalidCardinality.yang");
     }
 
@@ -131,7 +131,7 @@
     @Test
     public void processLeafMandatoryInvalidCardinality() throws IOException, ParserException {
         thrown.expect(ParserException.class);
-        thrown.expectMessage("YANG file error: Invalid cardinality of mandatory in leaf \"invalid-interval\".");
+        thrown.expectMessage("YANG file error: \"mandatory\" is defined more than once in \"leaf invalid-interval\".");
         YangNode node = manager.getDataModel("src/test/resources/LeafMandatoryInvalidCardinality.yang");
     }