Fix #404 - add Cunge (1980) to Walls, update doc

docs/en/calculators/structures/liste.md

docs/fr/calculators/structures/liste.md

jalhyd_branch

src/app/calculators/cloisons/config.json

src/app/calculators/cloisons/en.json

src/app/calculators/cloisons/fr.json

src/app/calculators/parallelstructure/config.json

src/app/calculators/parallelstructure/en.json

src/app/calculators/parallelstructure/fr.json

src/app/formulaire/elements/formulaire-node.ts

src/locale/messages.en.json

src/locale/messages.fr.json