[website] Allows the upload of a shared library for a binary algorithm

beat/web/algorithms/api.py

beat/web/algorithms/static/algorithms/css/editor.css

beat/web/algorithms/templates/algorithms/edition.html

beat/web/algorithms/templates/algorithms/panels/editor.html

beat/web/algorithms/templates/algorithms/view.html

beat/web/algorithms/views.py

beat/web/code/models.py

beat/web/common/texts.py

buildout.cfg