Merge branch 'doc-webapp' into 'master'

docs/components/custom-apps/web-app/feedback.md

docs/components/custom-apps/web-app/footer.md

docs/components/custom-apps/web-app/header.md

docs/components/custom-apps/web-app/homepage.md

docs/components/custom-apps/web-app/overview.md

docs/components/custom-apps/web-app/partners.md

docs/components/custom-apps/web-app/reuses.md

docs/components/custom-apps/web-app/search.md

docs/components/custom-apps/web-app/side-menu.md

docs/components/custom-apps/web-app/sign-up-in-out.md

docs/components/custom-apps/web-app/static-pages.md

docs/components/custom-apps/web-app/user-management.md

docs/components/off-the-shelf-apps/cms.md

docs/components/proxies/web-mapping-services.md

docs/components/services/authentication.md

docs/components/services/changelog.md

docs/components/services/credits.md

docs/components/services/mailer.md

docs/components/services/media-library.md

docs/components/services/organizations.md