YANG construct collision detection framework added

Change-Id: I1458f9e3192641f3f90c444798c31a64536ffa5d
diff --git a/utils/yangutils/src/test/resources/ContainerDuplicateContainer.yang b/utils/yangutils/src/test/resources/ContainerDuplicateContainer.yang
new file mode 100644
index 0000000..4928463
--- /dev/null
+++ b/utils/yangutils/src/test/resources/ContainerDuplicateContainer.yang
@@ -0,0 +1,23 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    container ospf {
+        container valid {
+            leaf invalid-interval {
+                type "uint16";
+                units "seconds";
+                status current;
+                reference "RFC 6020";
+            }
+        }
+        container valid {
+            leaf invalid-interval {
+                type "uint16";
+                units "seconds";
+                status current;
+                reference "RFC 6020";
+            }
+        }
+    }
+}