ONOS-574 - Complete REST APIs for flows

- codecs for all objects referenced by flows
- codecs for HostToHost and PointToPoint intents
- standardized on context.codec() rather than direct calls to new codec()

Change-Id: I94fcb6e31a9161132c6efc2793b9c46fa3cc4570
diff --git a/web/api/src/main/java/org/onosproject/codec/impl/HostCodec.java b/web/api/src/main/java/org/onosproject/codec/impl/HostCodec.java
index 9bb4c2e..843e030 100644
--- a/web/api/src/main/java/org/onosproject/codec/impl/HostCodec.java
+++ b/web/api/src/main/java/org/onosproject/codec/impl/HostCodec.java
@@ -34,7 +34,8 @@
     @Override
     public ObjectNode encode(Host host, CodecContext context) {
         checkNotNull(host, "Host cannot be null");
-        final JsonCodec<HostLocation> locationCodec = new HostLocationCodec();
+        final JsonCodec<HostLocation> locationCodec =
+                context.codec(HostLocation.class);
         final ObjectNode result = context.mapper().createObjectNode()
                 .put("id", host.id().toString())
                 .put("mac", host.mac().toString())