Resolve "Optimize Human Verification"

Closes #865

See merge request !1387

Tests need to be done!

Resolve "Member Key cannot be used with the search plugin"

Closes #862

See merge request !1378

Merge branch '862-member-key-cannot-be-used-with-the-search-plugin' of https://gitlab.metager3.de/open-source/MetaGer into 862-member-key-cannot-be-used-with-the-search-plugin

Development

See merge request !1382

Update public/img/hilfe-php-resultpic-en-01.png,...

See merge request !1373

Update resources/lang/de/spende.php, resources/views/spende/spende.blade.php,...

See merge request !1375