Feat/submodules

[adatzer]

A preview of the final outcome after merging and running the submodules_update github action can be seen in this temporary fork here.

[adatzer]

Thank you for reviewing @paulboocock ! Concerning the snowplow-iglu server helm chart, it would be great to reference as well. Indeed, though, submodules need to be git repositories, so we cannot add only the relevant subdirectory as a submodule. The alternatives i have considered so far are:

• Add the whole helm-charts repository as submodule under 3-infrastructure path, and make it update only on an snowplow-iglu-server/x.x.x release tag pattern. And in the readme table link to the relevant subdirectory.
• Add the relevant subdirectory as a simple directory under 3-infrastructure (not as a submodule). Then extend the submodules_update github actions workflow to make a diff and apply it as a patch, again on relevant release tag discovery.
• Only add another entry to the 3-infrastructure's Readme table.

Each of the above has its pros and cons and i am not sure which makes more sense. What do you think?

[adatzer]

The rebase force-pushed includes:

1. Reorder of commits to allow setting the new url for igluctl and iglu-server
2. Switch to snowplow.io domain (included in "Update Readme files" commit)
3. Cherry-pick of commit from https://github.com/snowplow/iglu/pull/483
4. Issue https://github.com/snowplow/iglu/issues/529

Temporary test repository with the rebased PR merged.