BAG extraction app for data-modules

[reinvantveer]

No fully functional module yet, just checking whether it is on the right track. Some issues:

• Haven't tested with the real BAG yet. But most ingredients are in place
• Haven't dealt with the address points yet. Will get to that.
• I don't plan on creating relations between BAG objects just yet, since I don't have a strategy yet. It could involve inserting everyting into Neo4j and run a join in there. It would require either a spatial join, or extraction of the "Verblijfsobjecten" which lists the connection between buildings and addresses.

[reinvantveer]

Oh yeah, now it's not too late yet, I would propose to do the chaining of dataset module execution through the resolving of promises. I think it would be better than passing in a write object, and let the module be responsible for its own writing. If anything, a configuration object could be passed in, but coupling the data modules to the ingestion process makes for hard debugging and difficult unit testing.

Of course this requires rewriting some of https://github.com/histograph/data