Enable javadoc checkstyle

and fix violations.

smack-experimental/src/main/java/org/jivesoftware/smackx/carbons/packet/Carbon.java

@@ -19,7 +19,7 @@ package org.jivesoftware.smackx.carbons.packet;
 import org.jivesoftware.smack.packet.SimpleIQ;
 
 /**
- * Carbon IQs
+ * Carbon IQs.
  */
 public class Carbon {
     public static final String NAMESPACE = "urn:xmpp:carbons:2";

smack-experimental/src/main/java/org/jivesoftware/smackx/csi/ClientStateIndicationManager.java

@@ -21,7 +21,8 @@ import org.jivesoftware.smack.XMPPConnection;
 import org.jivesoftware.smackx.csi.packet.ClientStateIndication;
 
 /**
- * 
+ * Manager for Client State Indication.
+ *
  * @see <a href="http://xmpp.org/extensions/xep-0352.html">XEP-0352: Client State Indication</a>
  *
  */

smack-experimental/src/main/java/org/jivesoftware/smackx/csi/packet/ClientStateIndication.java

@@ -20,7 +20,7 @@ import org.jivesoftware.smack.packet.FullStreamElement;
 import org.jivesoftware.smack.packet.ExtensionElement;
 
 /**
- * 
+ * Client State Indication.
  * @see <a href="http://xmpp.org/extensions/xep-0352.html">XEP-0352: Client State Indication</a>
  *
  */

smack-experimental/src/main/java/org/jivesoftware/smackx/hoxt/packet/AbstractHttpOverXmpp.java

@@ -246,7 +246,7 @@ public abstract class AbstractHttpOverXmpp extends IQ {
         private final String text;
 
         /**
-         * Creates this element.builder.toString();
+         * Creates this element.builder.toString().
          *
          * @param text value of text
          */

smack-experimental/src/main/java/org/jivesoftware/smackx/json/packet/JsonPacketExtension.java

@@ -19,7 +19,7 @@ package org.jivesoftware.smackx.json.packet;
 import org.jivesoftware.smack.packet.Stanza;
 
 /**
- * XMPP JSON Containers as defined in XEP-0335
+ * XMPP JSON Containers as defined in XEP-0335.
  *
  * @see <a href="http://xmpp.org/extensions/xep-0335.html">XEP-0335: JSON Containers</a>
  */