Simplify duplicate file handling in UploadResponder.
This prevents an infinite loop when files start with invalid characters, such as \0.
Provide a decent error message if test system does not exist.
Do properly handle null values in Escape directive.
Escape content in templates.
Remove unused properties file.
fix some error message. They can no longer contain html markup.
Fix upload responder test for java 7
Small improvement to symlink responder.