ONOS-4919: Implement RESTCONF client

Adding code to support RESTCONF protocol as one of
the supported SBI protocols of ONOS. This RESTCONF SBI extends
the current REST SBI protocl and adds some new APIs/functinalities
so that a provider can subscribe/register to an external restconf
server to receive notification stream.

Change-Id: I21bf0d0f0394cf788e066d743b3ade04735fe07e
diff --git a/protocols/rest/pom.xml b/protocols/rest/pom.xml
index ca42451..e62f956 100644
--- a/protocols/rest/pom.xml
+++ b/protocols/rest/pom.xml
@@ -39,4 +39,4 @@
     </dependencies>
 
 
-</project>
\ No newline at end of file
+</project>