Make sure non-spatial tabular datasets are described as Tables, not Vectors.

[davemfish]

sqlite .db files can be opened by GDAL as vector datasets. That can be inconvenient if the sqlite file is not a spatial database. Similar to the CSV case, just because GDAL can open it does not mean we want to describe the resource as a VectorResource instead of a TableResource.

[davemfish]

We might want to rethink how we determine the correct metadata model for a dataset. Perhaps checking for geometries, or coordinates, or something like that. In the interest of getting this right longer-term, I'm putting it in a 0.2.0 milestone.