Typeahead i18n support

[Giovanni-NL]

Is your feature request related to a problem? Please describe.

The typeahead feature adds an aria-live region which speaks "No results available" or "n result(s) available" depending on the status. This text is hard-coded and non-translatable.

Describe the solution you'd like

Please make it so that this text supports the standard Angular i18n translation feature so that I can add translations in my required languages to my translation files. For example, allow me to set ngb.typeahead.no-results and ngb.typeahead.results-available texts.

Code found in the current version of ngx-bootstrap typeahead.mjs
// live announcer
const count = results ? results.length : 0;
this._live.say(count === 0 ? 'No results available' : ${count} result${count === 1 ? '' : 's'} available);