import hdm4 data with specific columns

One of the key feedback we received is to build a utility to import HDM4 data. For our experiments in Zambia and Paraguay this data is not available. But it would be good to allow importing HDM4 with the following columns:

1. Road Name and/or Number
2. GIS Coordinate of start and end point of the road segment and road junctions
2. Length (km)
3. Population
4. Trafficvolume
5. Geometry
6. Road Condition

@ingalls what do you think? Since we don't have access to this data now, what I recommend is we build a command to import using a translation file to specify what columns from the CSV file should be associated to what columns in the database.

I think then the calculate command should probably use this over any other dataset if available.