bug#29321: Isearch hit count

[Charles A. Roelli]

> From: Juri Linkov <juri@linkov.net>
> Date: Mon, 05 Nov 2018 00:59:20 +0200
> 
> Here is a new version:
> 
> [isearch.count.6.el (344kB)]

Works great here.  Thanks for working on this, Juri.

Could we prevent the "0/0" count from showing when searching for an
incomplete regexp?  For example, typing characters after C-M-s [
results in the isearch prompt shifting when the "0/0" count is
displayed lazily after each keypress.

Also, the count is shown in the prompt even for "M-e".  For example,
C-s buf M-e shows "1/2 I-search:" as the (static) prompt, which is not
necessary (and it may be outdated as soon as the user changes the text
in the minibuffer).