Java wrapper code changes

Recently some significant changes have been merged to the VTK master branch for the Java wrapper code generation. The number of exported data types has been extended to include byte, short, long and float types, so that the generated methods closely match those in the VTK API. Overloaded function declarations are also now output. Array marshalling has been improved and the javac deprecation warnings have been eliminated.

It would be helpful if any developers building the Java wrappers from the master branch could try out the new code and give some feedback about any issues they run into.