Move non wiki related files out of wiki/src subdir

As we want to create a autopush for Weblate, it may be problematic, if scripts try to load configurations from directories and weblate drops a *po file into it.

List of files with executable flag:

find wiki -perm -u+rwx -type f | grep -v ".po$" 
wiki/src/lib/js/jquery.min.js
wiki/src/contribute/l10n_tricks/doc-whatchanged
wiki/src/contribute/l10n_tricks/transifex_translators.sh
wiki/src/contribute/l10n_tricks/language_statistics.sh
wiki/src/contribute/l10n_tricks/git-clean-po
wiki/src/contribute/l10n_tricks/unifyPo.py
wiki/src/contribute/how/documentation/compress-image.sh
wiki/src/contribute/how/documentation/qrcode-decode.sh
wiki/src/contribute/how/documentation/qrcode-encode.sh
wiki/src/blueprint/greeter_revamp_UI/mockups/mockup.py
wiki/src/blueprint/mumble-server

Related issues

• Related to #15402 (closed)

Original created by @Hefee on 16761 (Redmine)