Really old external packages in the default installation for pdf viewer


After a new install I have noticed that pdf.js is a really old version 1.1.215 that has several issues in decoding well formed PDF file.
I have locally updated the packages to v1.9.426 and pydio now works properly.
I will suggest the package maintainers to have a look to those external dependencies to keep pydio up-to-date.
Otherwise, likewise is done for other plugins, leave the user the duty to download and install latest release of the javascript library.