Add "cumulated" in the name of scripts to export cumulated working groups

I also added "cumulated" in the name of files generated with exported
data and I updated the script accordingly.

The former names will be reused for new scripts which export 3 distinct
categories for working groups 1, 2, and 3, rather than 7 categories for
the cumulated working groups 1+2+3, 1+2, 1+3, etc.
Add SQL scripts for all filters and grouping

These scripts provide all the data necessary to the IPCC Tool
interface in its current state.

Besides scripts to export categories for filters and grouping,
one script exports the list of years of assessment reports.