Added ViewClient java launcher

- Version 2.3.15
- dump moved to tools
- dump-simple.py and dump-simple-lib.py examples created
- dump.py prints notice
- dump-all-windows-lib.py example created
- updated build.xml to produce mixed java/python jar
viewclient.py: added more verbose error message
ViewClient: Preserved spaces in command line (if exist) using the array form of exec()

- Improved javadoc
- Added error message for Windows (not shebang on such platform)