Install/configure locales

[probonopd]

FreeBSD% ./SuperSlicer-ubuntu_18.04-gtk2-2.4.58.2.AppImage --appimage-extract-and-run
Initializing StaticPrintConfigs
An error occured while setting up locale.
You may need to reconfigure the missing locales, likely by running the "locale-gen" and "dpkg-reconfigure locales" commands.
SuperSlicer will now terminate.

locale::facet::_S_create_c_locale name not valid

Workaround:

FreeBSD% export LOCALE=C
FreeBSD% export LANG=C  
FreeBSD% ./SuperSlicer-ubuntu_18.04-gtk2-2.4.58.2.AppImage --appimage-extract-and-run