Visualisation page is broken when dataflow doen't have a time period
here is an example of non working usecase: https://de-qa.siscc.org/vis?lc=en&df%5Bds%5D=qa%3Astable&df%5Bid%5D=DF_CARTEL&df%5Bag%5D=OECD&df%5Bvs%5D=1.0&av=true&ac=false
here is an example of non working usecase: https://de-qa.siscc.org/vis?lc=en&df%5Bds%5D=qa%3Astable&df%5Bid%5D=DF_CARTEL&df%5Bag%5D=OECD&df%5Bvs%5D=1.0&av=true&ac=false