Revert "Bump yang tools version to 2.4"

This reverts commit 5193cb736c41d52f6007e7e2bdfd619b7598604f.

Change-Id: If061ca507f702f161fa112188abd26aa4924618d
diff --git a/lib/BUCK b/lib/BUCK
index 8021a3d..f7cb757 100644
--- a/lib/BUCK
+++ b/lib/BUCK
@@ -1,4 +1,4 @@
-# ***** This file was auto-generated at Fri, 16 Feb 2018 17:18:31 GMT. Do not edit this file manually. *****
+# ***** This file was auto-generated at Sat, 17 Feb 2018 00:32:25 GMT. Do not edit this file manually. *****
 # ***** Use onos-lib-gen *****
 
 pass_thru_pom(
@@ -1340,55 +1340,55 @@
 
 remote_jar (
   name = 'onos-yang-model',
-  out = 'onos-yang-model-2.4.1.jar',
-  url = 'mvn:org.onosproject:onos-yang-model:jar:2.4.1',
-  sha1 = '3e9bce9e34b8cd48e35db9f5f1b7bcf02272cc94',
-  maven_coords = 'org.onosproject:onos-yang-model:2.4.1',
+  out = 'onos-yang-model-2.3.1.jar',
+  url = 'mvn:org.onosproject:onos-yang-model:jar:2.3.1',
+  sha1 = 'ffe8a79368ae816220a47bb9cad39e2d48ae415d',
+  maven_coords = 'org.onosproject:onos-yang-model:2.3.1',
   visibility = [ 'PUBLIC' ],
 )
 
 remote_jar (
   name = 'onos-yang-compiler-api',
-  out = 'onos-yang-compiler-api-2.4.1.jar',
-  url = 'mvn:org.onosproject:onos-yang-compiler-api:jar:2.4.1',
-  sha1 = '84c8a4ff5275673bb250aee386ad101efa9ffd1f',
-  maven_coords = 'org.onosproject:onos-yang-compiler-api:2.4.1',
+  out = 'onos-yang-compiler-api-2.3.1.jar',
+  url = 'mvn:org.onosproject:onos-yang-compiler-api:jar:2.3.1',
+  sha1 = '11edae3442f9fc8b4cb69aec2004203189fb3034',
+  maven_coords = 'org.onosproject:onos-yang-compiler-api:2.3.1',
   visibility = [ 'PUBLIC' ],
 )
 
 remote_jar (
   name = 'onos-yang-runtime',
-  out = 'onos-yang-runtime-2.4.1.jar',
-  url = 'mvn:org.onosproject:onos-yang-runtime:jar:2.4.1',
-  sha1 = '1bafc4fa6121a8f5704875f5f314651d368edf4a',
-  maven_coords = 'org.onosproject:onos-yang-runtime:2.4.1',
+  out = 'onos-yang-runtime-2.3.1.jar',
+  url = 'mvn:org.onosproject:onos-yang-runtime:jar:2.3.1',
+  sha1 = 'b5da218f5841a39787aff51a58d154a76f07d249',
+  maven_coords = 'org.onosproject:onos-yang-runtime:2.3.1',
   visibility = [ 'PUBLIC' ],
 )
 
 remote_jar (
   name = 'onos-yang-serializers-json',
-  out = 'onos-yang-serializers-json-2.4.1.jar',
-  url = 'mvn:org.onosproject:onos-yang-serializers-json:jar:2.4.1',
-  sha1 = '78fa5693549453c1ead06404196c14db06abb82e',
-  maven_coords = 'org.onosproject:onos-yang-serializers-json:2.4.1',
+  out = 'onos-yang-serializers-json-2.3.1.jar',
+  url = 'mvn:org.onosproject:onos-yang-serializers-json:jar:2.3.1',
+  sha1 = '8f101d36ebcb14176121ddfddd15599c07967138',
+  maven_coords = 'org.onosproject:onos-yang-serializers-json:2.3.1',
   visibility = [ 'PUBLIC' ],
 )
 
 remote_jar (
   name = 'onos-yang-serializers-xml',
-  out = 'onos-yang-serializers-xml-2.4.1.jar',
-  url = 'mvn:org.onosproject:onos-yang-serializers-xml:jar:2.4.1',
-  sha1 = '42e43a7ede05451d94107d185d6658c57a72baf5',
-  maven_coords = 'org.onosproject:onos-yang-serializers-xml:2.4.1',
+  out = 'onos-yang-serializers-xml-2.3.1.jar',
+  url = 'mvn:org.onosproject:onos-yang-serializers-xml:jar:2.3.1',
+  sha1 = '58090e77105c6f0cbf594b7130263056d4f9a473',
+  maven_coords = 'org.onosproject:onos-yang-serializers-xml:2.3.1',
   visibility = [ 'PUBLIC' ],
 )
 
 remote_jar (
   name = 'onos-yang-serializers-utils',
-  out = 'onos-yang-serializers-utils-2.4.1.jar',
-  url = 'mvn:org.onosproject:onos-yang-serializers-utils:jar:2.4.1',
-  sha1 = '8fa9c76821c976f42b548794caeda69e9391facc',
-  maven_coords = 'org.onosproject:onos-yang-serializers-utils:2.4.1',
+  out = 'onos-yang-serializers-utils-2.3.1.jar',
+  url = 'mvn:org.onosproject:onos-yang-serializers-utils:jar:2.3.1',
+  sha1 = '58d6d3a6b10e236b1b65230a02cd7c2389478645',
+  maven_coords = 'org.onosproject:onos-yang-serializers-utils:2.3.1',
   visibility = [ 'PUBLIC' ],
 )