* fix: removal of timeago fallback middleware
Instead of loading English fallback on missing language, we opt
to not send a script tag for a missing language to begin with.
Timeago already loads with English as default, so it will just
continue to use English.
* fix: check userLang against supported language codes
* fix: cleaned up code as per @pitaj
* fix: added comments
* fix: more fixes as per @pitaj
* feat: added addl. test for timeago locales, fixed broken test