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>

src/wheelencoder/wheelencoder.cxx

@@ -24,9 +24,6 @@
 
 #include <iostream>
 
-#ifdef JAVACALLBACK
-#undef JAVACALLBACK
-#endif
 #include "wheelencoder.hpp"
 
 using namespace upm;