Add support for STIB (Brussle)

[6543]

Acknowledgments
Please check the following boxes with an x if they apply:

• The feature I want to propose would be useful for the majority of users, not only for me personally.
• I am aware that Transportr is mostly developed by one person in their unpaid spare time.
• I can help myself to get this feature implemented or know someone who wants to do it.
• If I want to add support for a new region or country, I checked that this is already available in public-transport-enabler and know the process described on the Transportr homepage.

Is your feature request related to a problem? Please describe.
It would be nice to have https://www.stib-mivb.be/index.htm?l=en covered by transportr

Describe the solution you'd like
Add STIB next to all other providers ...

Describe alternatives you've considered
Well osm~and do know the lines and you can get somehow infro via that. But the routing is completly broken.

Additional context
Noticed while attending fosdem

[Altonss]

This is an upstream issue, if you want support for STIB for now the only way would be to add it in https://github.com/schildbach/public-transport-enabler/.

[6543]

ok created an upstream issue: schildbach/public-transport-enabler#561