Discovery: Find all required sources to generate our own index database

Part of the work to move from gemojione data files completely and be able to move our unicode support to the latest 13.1, is to be able to identify all the required data-sources from Unicode own specification.

When doing my research trying to figure out how other indexes were being compiled, they never came with a proper answer nor they came with the actual code/tools used to do that.

It seems that everyone is doing a set of ETL operations but not in a structured way that it can be easily released as a production code.

The goal here is to find and vendorize the sources needed to generate our own index file.