Add NI Water Quality Sample Data

[andrewbolster]

NI Water has a per-postcode query UI for HTML-tabular (and human understandable) water quality data.

There should be a way to (kindly) bulk query these in the most efficient (i.e. not involving 50k queries).

There are also "predictable" report links included in this output that can reference the more detailed data available.

Should be able to get a querable dataframe for presented factors such as 'NI Hardness Classification'

[andrewbolster]

Can get the PostCode to Water Supply Zone mapping from here, so that drops the query space from 50k to 56. That'll do. But you don't get the nice table UI out of that...

[andrewbolster]

So... turns out that the query on that page is

https://www.niwater.com/water-quality-lookup.ashx?p=BT71RY

However... after a little manual enumeration, using the z query parameter appears to work directly

https://www.niwater.com/water-quality-lookup.ashx?z=ZS0107

[andrewbolster]

Got hardness

Will update with PR later!