[cesu] Do not download unavailable documents
Some documents are not ready to be downloaded, and when trying to download them it results in a 500 error. When now apply the same logic as in the site to decide if a document should be listed or not.
Some documents are not ready to be downloaded, and when trying to download them it results in a 500 error. When now apply the same logic as in the site to decide if a document should be listed or not.