Add support for importing data in diva format
We got data from the IVB in diva format.
It is necessary to convert the data to GTFS format, so we can import it (similar to using vdv data).
There is a github project that is able to convert diva to gtfs:
https://github.com/stkdiretto/diva2gtfs
However, this needs a sqlite database for conversion so we have to extend the osmPti2mmds script