Add ability to choose the language

client/src/app/app.component.html

client/src/app/app.component.scss

client/src/app/app.module.ts

client/src/app/menu/language-chooser.component.html

client/src/app/menu/language-chooser.component.scss

client/src/app/menu/language-chooser.component.ts

client/src/app/menu/menu.component.html

client/src/app/menu/menu.component.scss

client/src/app/menu/menu.component.ts

client/src/assets/images/menu/language.png

client/src/sass/application.scss

client/src/sass/include/_variables.scss

package.json

server.ts

server/controllers/client.ts

shared/models/i18n/i18n.ts

yarn.lock