Add infrastructure for Korean

Update i18n files/scripts to support Korean in advance of translation work from Terry.

Specifically:

• Add moment.js locale for "ko" (Korean)
• Remove remaining language references in scripts where possible so they're more language-agnostic (did some here: https://github.com/openshift/console/pull/7030; blocked until this merges)
• Update bash script from https://github.com/openshift/console/pull/7030 to export Korean po files
• Add timestamp format in "ko" folder in public/locales