Use fixup_name function to normalize field names

[ridoo]

Closes #26

[mwallschlaeger]

look good to me

[mwallschlaeger]

When testing this PR i faced the issue that the description and labels are not transferred to the attribute table in geonode.

[mwallschlaeger]

Patching the API is not removing the attribute description and label. So the initial problem is fixed ...

[ridoo]

Patching the API is not removing the attribute description and label. So the initial problem is fixed ...

Normalizing attribute names now match the layer attributes known by GeoServer. However, it turns out that sync'ing GeoNode state with GeoServer is not possible via GeoNode tools (only the other direction, i.e. GeoServer -> GeoNode -- even when editing the attributes via metadata editor).

However, for now, we do not use set_attributes and store the actual values directly via Attribute model.

I also played around with setting the layer's extent so that GeoServer has some valid boundaries. However, using VRT does not have any effect here, so we'd have to force GeoServer via REST API to calculate the layers boundaries. This, however, can only be done (as far as I know) via PUTting the actual feature type description, optionally passing the recalculate parameter.