SWIGJAVA: Remove the last JAVA ifdefs from src

Removed all references to #ifdef SWIGJAVA and JAVACALLBACK from the
library source.  All java-specific source code has been moved to the
corresponding library's .i file for java.

    * Update library source
    * Update examples where necessary
    * The function pointer methodology has been remove from libraries
      which provided callbacks as both a class and a function pointer
      implementation.  Examples were updated to use the class version
      of callbacks.
    * Updated documentation for SWIGJAVA

Signed-off-by: Noel Eck <noel.eck@intel.com>

examples/c++/pulsensor.cxx

@@ -42,17 +42,24 @@ sig_handler(int signo)
     }
 }
 
-void
-handler(clbk_data data)
+
+//! [Interesting]
+class mycb : public virtual Callback
 {
-    printf("callback data (%d)\n", data.is_heart_beat);
-}
+    public:
+        virtual void run(clbk_data arg)
+        {
+            printf("callback data (%d)\n", arg.is_heart_beat);
+        }
+};
+
 
 int
 main(int argc, char** argv)
 {
+    mycb cb;
     //! [Interesting]
-    Pulsensor sensor(handler);
+    Pulsensor sensor(&cb);
 
     sensor.start_sampler();
     while (!doWork) {