Security updates for Monday

Security updates have been issued by Arch Linux (firefox, libreoffice-still, nginx, nginx-mainline, and subversion), Debian (commons-beanutils, h2o, libapache2-mod-auth-openidc, libmspack, qemu, squid, and tiff), Fedora (kubernetes, libmodbus, nfdump, and nodejs), openSUSE (dkgpg, libTMCG, go1.12, neovim, python, qbittorrent, schismtracker, teeworlds, thunderbird, and zstd), and SUSE (go1.11, go1.12, python-SQLAlchemy, and python-Twisted).