Updating Yang tools to 2.6

Change-Id: Ib511bbbd0793fd110902ab307812af6eefca4d70
diff --git a/lib/pom.xml b/lib/pom.xml
index dbbb80c..bf3a47a 100644
--- a/lib/pom.xml
+++ b/lib/pom.xml
@@ -44,7 +44,7 @@
         <netty4.version>4.1.8.Final</netty4.version>
         <openflowj.version>3.2.1.onos</openflowj.version>
         <onos-maven-plugin.version>1.12</onos-maven-plugin.version>
-        <onos-yang-tools.version>2.5</onos-yang-tools.version>
+        <onos-yang-tools.version>2.6</onos-yang-tools.version>
         <osgi.version>5.0.0</osgi.version>
         <karaf.version>3.0.8</karaf.version>
         <jersey.version>2.26</jersey.version>