search-input enhanced:
- placeholder can be set from outside
- quick search results are links containing a target url to navigate to
- showing and hiding of quick search results not when focus or blur, but only when clicking outside the input => when leaving a browser window the quick search results are still shown
- when clicking in a search-input that already contains text, the results are not reloaded, but they only show up again

BUG: when leaivng the input via tab the quick search result box remains visible
- added Utils with function assert
- search-input tab and click implemented