Bump commons lang to v3 for Gerrit on stable-3.6

Change-Id: Id7acdaf6344062f3cd51329e1f16d33e4a858cbf
diff --git a/src/main/java/com/cisco/gerrit/plugins/slack/client/WebhookClient.java b/src/main/java/com/cisco/gerrit/plugins/slack/client/WebhookClient.java
index 81287b2..fddbec7 100644
--- a/src/main/java/com/cisco/gerrit/plugins/slack/client/WebhookClient.java
+++ b/src/main/java/com/cisco/gerrit/plugins/slack/client/WebhookClient.java
@@ -30,7 +30,7 @@
 import java.net.URL;
 import java.nio.charset.StandardCharsets;
 import java.util.Scanner;
-import org.apache.commons.lang.StringUtils;
+import org.apache.commons.lang3.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
diff --git a/src/main/java/com/cisco/gerrit/plugins/slack/message/ChangeMergedMessageGenerator.java b/src/main/java/com/cisco/gerrit/plugins/slack/message/ChangeMergedMessageGenerator.java
index ce646b5..69813ed 100644
--- a/src/main/java/com/cisco/gerrit/plugins/slack/message/ChangeMergedMessageGenerator.java
+++ b/src/main/java/com/cisco/gerrit/plugins/slack/message/ChangeMergedMessageGenerator.java
@@ -17,7 +17,7 @@
 
 package com.cisco.gerrit.plugins.slack.message;
 
-import static org.apache.commons.lang.StringUtils.substringBefore;
+import static org.apache.commons.lang3.StringUtils.substringBefore;
 
 import com.cisco.gerrit.plugins.slack.config.ProjectConfig;
 import com.google.gerrit.server.events.ChangeMergedEvent;
diff --git a/src/main/java/com/cisco/gerrit/plugins/slack/message/CommentAddedMessageGenerator.java b/src/main/java/com/cisco/gerrit/plugins/slack/message/CommentAddedMessageGenerator.java
index 6f8775a..4cd608c 100644
--- a/src/main/java/com/cisco/gerrit/plugins/slack/message/CommentAddedMessageGenerator.java
+++ b/src/main/java/com/cisco/gerrit/plugins/slack/message/CommentAddedMessageGenerator.java
@@ -17,7 +17,7 @@
 
 package com.cisco.gerrit.plugins.slack.message;
 
-import static org.apache.commons.lang.StringUtils.substringBefore;
+import static org.apache.commons.lang3.StringUtils.substringBefore;
 
 import com.cisco.gerrit.plugins.slack.config.ProjectConfig;
 import com.google.gerrit.server.data.ChangeAttribute;
diff --git a/src/main/java/com/cisco/gerrit/plugins/slack/message/PatchSetCreatedMessageGenerator.java b/src/main/java/com/cisco/gerrit/plugins/slack/message/PatchSetCreatedMessageGenerator.java
index 4aae685..6b7db05 100644
--- a/src/main/java/com/cisco/gerrit/plugins/slack/message/PatchSetCreatedMessageGenerator.java
+++ b/src/main/java/com/cisco/gerrit/plugins/slack/message/PatchSetCreatedMessageGenerator.java
@@ -17,7 +17,7 @@
 
 package com.cisco.gerrit.plugins.slack.message;
 
-import static org.apache.commons.lang.StringUtils.substringBefore;
+import static org.apache.commons.lang3.StringUtils.substringBefore;
 
 import com.cisco.gerrit.plugins.slack.config.ProjectConfig;
 import com.google.gerrit.extensions.client.ChangeKind;
diff --git a/src/main/java/com/cisco/gerrit/plugins/slack/message/PrivateStateChangedGenerator.java b/src/main/java/com/cisco/gerrit/plugins/slack/message/PrivateStateChangedGenerator.java
index 625729e..fe828e5 100644
--- a/src/main/java/com/cisco/gerrit/plugins/slack/message/PrivateStateChangedGenerator.java
+++ b/src/main/java/com/cisco/gerrit/plugins/slack/message/PrivateStateChangedGenerator.java
@@ -17,7 +17,7 @@
 
 package com.cisco.gerrit.plugins.slack.message;
 
-import static org.apache.commons.lang.StringUtils.substringBefore;
+import static org.apache.commons.lang3.StringUtils.substringBefore;
 
 import com.cisco.gerrit.plugins.slack.config.ProjectConfig;
 import com.google.gerrit.server.events.PrivateStateChangedEvent;
diff --git a/src/main/java/com/cisco/gerrit/plugins/slack/message/ReviewerAddedMessageGenerator.java b/src/main/java/com/cisco/gerrit/plugins/slack/message/ReviewerAddedMessageGenerator.java
index 2a42c58..ba91143 100644
--- a/src/main/java/com/cisco/gerrit/plugins/slack/message/ReviewerAddedMessageGenerator.java
+++ b/src/main/java/com/cisco/gerrit/plugins/slack/message/ReviewerAddedMessageGenerator.java
@@ -17,7 +17,7 @@
 
 package com.cisco.gerrit.plugins.slack.message;
 
-import static org.apache.commons.lang.StringUtils.substringBefore;
+import static org.apache.commons.lang3.StringUtils.substringBefore;
 
 import com.cisco.gerrit.plugins.slack.config.ProjectConfig;
 import com.google.gerrit.server.data.ChangeAttribute;
diff --git a/src/main/java/com/cisco/gerrit/plugins/slack/message/WorkInProgressStateChangedGenerator.java b/src/main/java/com/cisco/gerrit/plugins/slack/message/WorkInProgressStateChangedGenerator.java
index a5ec1da..c045158 100644
--- a/src/main/java/com/cisco/gerrit/plugins/slack/message/WorkInProgressStateChangedGenerator.java
+++ b/src/main/java/com/cisco/gerrit/plugins/slack/message/WorkInProgressStateChangedGenerator.java
@@ -17,7 +17,7 @@
 
 package com.cisco.gerrit.plugins.slack.message;
 
-import static org.apache.commons.lang.StringUtils.substringBefore;
+import static org.apache.commons.lang3.StringUtils.substringBefore;
 
 import com.cisco.gerrit.plugins.slack.config.ProjectConfig;
 import com.google.gerrit.server.events.WorkInProgressStateChangedEvent;