Table should contain some geometry information

[jongleur1983]

see tyrasd#18 (comment)

"The table should also contain some geometry information. Probably, a geometry column containing WKT, or at least lat/lon columns for POIs."

[jongleur1983]

partly solved: Geometry column is available and working, but for really complex geometries much memory and time is needed.
Currently WKT is calculated always, even when the column isn't visible. This should be done on demand - or on-demand for complex geometries

[jongleur1983]

WKT code fixed in f392ad9