crs:4326 vs crs:'4326' in iso19139

[pvgenuchten]

pygeometa's feature to use a geometry with poslist (instead of east,west,north,south) if the crs is not 4326 also triggers if the crs is '4326' (string).

tools like pycsw currently only support the east,west,north,south format

suggestion is to run float(crs) before making the check