Use variable for maximum number of suggestions for quicksearch.
And hide suggestions when search field is emptied, or when no suggestion are found.

When the search input is still only a few characters, the number of matching pages is big.
Browsers have heavy work to progress this whole return, better cut off so only the part that is directly displayed will be sent.

This should make migrating from MediaWiki a bit easier.

This reverts commit f2cb3ec7.

Turns out I was too fast merging this. I can't get PHP's bzip handler to
handle a bzip1 compressed file.

in fact .tbz is tar.bz (bzip1) and .tbz2 is what tar.bz2 is used
commonly.

Before this change the GIF wasn't sent at all when the PHP settings
indicate that sending of the GIF needs to be deferred and it was sent
when the debug output was on.

  - removed some dead/unused code
  - fixed phpdoc
  - added typing on methods

the function always returned true, even if no action was taken. This
resulted in no further indexer tasks being run.

fixes the problem with missing innerText in Firefox (and other browsers)
and corrects shortening in regard to paddings and the use of the
text-overflow attribute