Currently translated at 86.0% (664 of 772)

Currently translated at 85.6% (661 of 772)

This allows better passing it as return value and consolidates all
access to it's values.

It also returns project and subproject.

This attribute can be True/False/None, where None means that both
options are possible.

We only need language code and filename from this function, the hash
was never used.

It really does not belong to models.