WIP: revamp html/css: sidebar, hamburger, templates

app/models/events.py

app/scodoc/sco_saisie_excel.py

app/scodoc/sco_saisie_notes.py

app/static/css/scodoc.css

app/static/css/scodoc97.css

app/static/icons/back.svg

app/templates/hamburger_menu.j2

app/templates/sco_page.j2

app/templates/sco_page_dept.j2

app/templates/scolar/index.j2

app/templates/sidebar.j2

app/views/notes.py

app/views/scolar.py

sco_version.py