Adding OpenConfig YANG models.

Change-Id: I0a2fdd5826e80933cf4b9ae939ff3051acec02aa
diff --git a/models/openconfig/src/main/yang/ospf/openconfig-ospfv2-common.yang b/models/openconfig/src/main/yang/ospf/openconfig-ospfv2-common.yang
new file mode 100644
index 0000000..6510816
--- /dev/null
+++ b/models/openconfig/src/main/yang/ospf/openconfig-ospfv2-common.yang
@@ -0,0 +1,79 @@
+submodule openconfig-ospfv2-common {
+
+  belongs-to openconfig-ospfv2 {
+    prefix "oc-ospfv2";
+  }
+
+  import openconfig-extensions { prefix "oc-ext"; }
+
+  // meta
+  organization "OpenConfig working group";
+
+  contact
+    "OpenConfig working group
+    www.openconfig.net";
+
+  description
+    "This submodule provides OSPFv2 configuration and operational
+    state parameters that are shared across multiple contexts";
+
+  oc-ext:openconfig-version "0.1.0";
+
+  revision "2017-02-28"{
+    description
+      "Initial public release of OSPFv2";
+    reference "0.1.0";
+  }
+
+  revision "2016-06-24" {
+    description
+      "Initial revision";
+    reference "0.0.1";
+  }
+
+  grouping ospfv2-common-mpls-igp-ldp-sync-config {
+    description
+      "Configuration parameters used for OSPFv2 MPLS/IGP
+      synchronization";
+
+    leaf enabled {
+      type boolean;
+      description
+        "When this leaf is set to true, do not utilise this link for
+        forwarding via the IGP until such time as LDP adjacencies to
+        the neighbor(s) over the link are established.";
+    }
+
+    leaf post-session-up-delay {
+      type uint32;
+      units milliseconds;
+      description
+        "This leaf specifies a delay, expressed in units of milliseconds,
+        between the LDP session to the IGP neighbor being established, and
+        it being considered synchronized by the IGP.";
+    }
+  }
+
+  grouping ospfv2-common-timers {
+    description
+      "Common definition of the type of timers that the OSPFv2 implementation
+      uses";
+
+    leaf timer-type {
+      type enumeration {
+        enum LINEAR_BACKOFF {
+          description
+            "The backoff used by the OSPFv2 implementation is linear, such that
+            a common delay is added following each event.";
+        }
+        enum EXPONENTIAL_BACKOFF {
+          description
+            "The backoff used by the OSPFv2 implementation is exponential, such
+            that the delay added following each event increases.";
+        }
+      }
+      description
+        "The timer mode that is utilised by the implementation.";
+    }
+  }
+}
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