extend translations and update German language

@benfry, here is the re-submit of the that updated [pull](https://github.com/processing/processing/pull/2933#issuecomment-63135574):

- Added translations for ...
  - undo+redo+action menu
  - export frame
  - new+rename+delete context menu
  - debugger and editor
- Updated structure of all languages
- Extended and improved German language
- Extended [Language](https://github.com/voidplus/processing/blob/17a0125ae4d011047693960ac8b5856ab26f6716/app/src/processing/app/Language.java) class with [a tiny debug feature for developing](https://github.com/voidplus/processing/blob/17a0125ae4d011047693960ac8b5856ab26f6716/app/src/processing/app/Language.java#L125). Set `Base.DEBUG = true` to copy/overwrite/update all languages each time.

Happy coding,
Darius