NOT TESTED YET! Buildscript has not finished yet (needed about 18h until now).
Made `data/v2/__init__.py` and `config/local.py` python3 compatible.
Writen helper functions because of repeating code:
+ `process_csv`
+ `build_generic`
useage demonstrated with `_build_languages`.
Writen `with_iter` for closing files automatical
when the processing has finished.
Writen for each group of models a function (named `build_`groupname)
and a function `build_all` which calls these functions.