Proposal: Rename repo to c2pa-cpp given its current purpose

[scouten-adobe]

Given this repo's current purpose (C++ builds, not C), I'd like to consider renaming the repo.

GitHub is generally very good at forwarding requests from an old URL to a new one, so this change theoretically shouldn't break much.

Posting the issue here to solicit feedback about any implications I might not be aware of.

[tmathern]

(It will break builds for those who use cmake to retrieve this repo's code/content as dependency in their builds. We need to give advance notice on the Discord servers before doing any renaming here).

[tmathern]

@scouten-adobe What if, instead, we create a c2pa-cpp repo, and migrate to this one, clearly indicating this one is deprecated and going to be archived? That gives people time to migrate, and is less "breaking-change-y"?

[scouten-adobe]

Reminder from @crandmck that we will need to update documentation when this is done.

[github-jira-sync-bot]

✅ Jira issue https://jira.corp.adobe.com/browse/CAI-10708 is successfully created for this GitHub issue.