Add Connection methods to ManagedConnection

The method for the Connection should be added as package private on the ManagedConnection, and the call should be delegated.

AcmeConnectionImpl:

public String callMe()
{
   return mc.callMe();
}

AcmeManagedConnection:

String callMe()
{
   return "HelloWorld !";
}

The method signatures should be the same, with regards to return type (void, ...), parameters and exceptions.