Moved temp directory and delete of temp file on delete in editor.

- Moved the temporary directory to the shared content directory.
- Implmented deleting of the temporary file from the server on delete from the editor.

Temp files stil need to be deleted when the editor is closed (should be done when the close button is impleented), when a resource is saved (i.e. the temp file is no longer needed) and on a schedule (for fringe cases).
Method to delete old temp files.
Implemented a ServletContextListener to clean up the temp files.
Changed the temp file deletion method to accept a list of files to delete.
Merge pull request #46 from AllTheDucks/fix-temp-file-upload

Fix temp file upload