Brand the webmail INBUXA: name, mark and wordmark

INBUXA is a product suite and ihasmail an independent product, so INBUXA's
webmail says INBUXA: the sign-in page, header, page title, installed-app name
and About page. The wordmark is drawn in the current text color. ihasmail's
version and AGPL source line stay as its credit. Two new strings, in all nine
catalogues; three Stalwart-only ones are no longer used.

web/src/locales/nl.ts

@@ -1213,6 +1213,8 @@ export const catalog: Catalog = {
     "Could not save filters: {error}": "Filters opslaan mislukt: {error}",
     "Could not send the receipt: {error}": "De leesbevestiging kon niet worden verzonden: {error}",
     "Could not sign in.": "Aanmelden mislukt.",
+    "About INBUXA webmail": "Over INBUXA webmail",
+    "Mail server": "Mailserver",
     "You'll enter your password on your mail server's sign-in page.": "U voert uw wachtwoord in op de aanmeldpagina van uw mailserver.",
     "You'll sign in on your mail server's own page.": "U meldt zich aan op de eigen pagina van uw mailserver.",
     "This sign-in didn't start in this browser. Try again.": "Deze aanmelding is niet in deze browser begonnen. Probeer het opnieuw.",