feat: add tooltips in administration forms

...admin-oai-set-form/admin-oai-set-form.presentational.html

...s/admin-oai-set-form/admin-oai-set-form.presentational.ts

...admin-orgunit-form/admin-orgunit-form.presentational.html

...s/admin-orgunit-form/admin-orgunit-form.presentational.ts

...s/admin-person-form/admin-person-form.presentational.html

...omponents/routables/deposit-file/deposit-file.routable.ts

src/assets/i18n/de.json

src/assets/i18n/en.json

src/assets/i18n/fr.json

src/environments/environment.defaults.ts