i2ptunnel: Add subsession support to servers, no UI yet

Update subsession javadocs

core/java/src/net/i2p/client/I2PSession.java

@@ -272,8 +272,10 @@ public interface I2PSession {
     public List<I2PSession> getSubsessions();
 
     /**
-     * Actually connect the session and start receiving/sending messages
-     *
+     * Actually connect the session and start receiving/sending messages.
+     * Connecting a primary session will not automatically connect subsessions.
+     * Connecting a subsession will automatically connect the primary session
+     * if not previously connected.
      */
     public void connect() throws I2PSessionException;
 

core/java/src/net/i2p/client/impl/I2PSessionImpl.java

@@ -548,6 +548,10 @@ public abstract class I2PSessionImpl implements I2PSession, I2CPMessageReader.I2
      * Disconnect / destroy from another thread may be called simultaneously and
      * will (should?) interrupt the connect.
      *
+     * Connecting a primary session will not automatically connect subsessions.
+     * Connecting a subsession will automatically connect the primary session
+     * if not previously connected.
+     *
      * @throws I2PSessionException if there is a configuration error or the router is
      *                             not reachable
      */

core/java/src/net/i2p/client/impl/SubSession.java

@@ -93,6 +93,9 @@ class SubSession extends I2PSessionMuxedImpl {
      * Disconnect / destroy from another thread may be called simultaneously and
      * will (should?) interrupt the connect.
      *
+     * Connecting a subsession will automatically connect the primary session
+     * if not previously connected.
+     *
      * @throws I2PSessionException if there is a configuration error or the router is
      *                             not reachable
      */