This commit contains a complete rewrite of find console utility.
The goal of it was to make the source code easier to maintain
and to add a missing feature (/offline switch).
Additional changes:
* now the program operates on Unicode strings;
* added conutils and shlwapi as program's libraries;
* added IDS_INVALID_SWITCH string into resources;
* modified IDS_USAGE string to include /offline switch
description.
https://ss64.com/nt/find.html was used for reference.
