Add querying of a CSV file defined by a URL

[simoc]

Add querying of CSV files from a URL. This will enable Google Sheets spreadsheets (and other data publicly available on the internet as CSV files) to be queried directly, without first downloading to a local CSV file.

This Stackoverflow question explains how to determine the URL for downloading a Google Sheets spreadsheet as a CSV file.

Maybe the JDBC connection string could be something like:

jdbc:relique:csv:url:https://docs.google.com/spreadsheets/d/KEY/export%3Fformat=csv%26gid=SHEET_ID

It is not clear how multiple CSV files from the same database connection can be supported, or whether that makes sense.