[Azoth CH] Don't double-install translations.
[Util] Added FindNotification::clear().
[Azoth CH] Added ChatFindBox for #1599.
[Azoth CH] Migrate to ChatFindBox for #1599.
[Azoth CH] Old code removed.
[Util] Proper flag values for FindNotification.
[Azoth CH] Internal support for case sensitive search in storage.

For #1599.

Such a kludge. SQLite is such a crap, `PRAGMA case_sensitive_like` doesn't
work at all for unicode stuff even with ICU-enabled builds.
[Azoth CH] Support case-sensitive search for #1599.
[Azoth CH] Code style fix.
[Azoth CH] Search scope check.