P&C-iso to IETF BCP 47 language tag: a cached array
This MR implement a new array in the database named $isolang .
You can use this array this way: isolang[
lang] where $lang is a
Pepper&Carrot lang. The result will be a IETF BCP 47 language tag
formated lang (depending the information found in 0_sources/langs.json)
This tag is used right now to fill the lang="" in the first html tag. It might be used later for more things.
Fix #18
Ref: #2 (closed)