Initial commit of Cisco's open source LMS

[ashman-p]

This is the initial commit. The following commits should have more weighty code additions.

Fixes #1098.

• [N] Does this PR change the input/output behaviour of a cryptographic algorithm (i.e., does it change known answer test values)? (If so, a version bump will be required from x.y.z to x.(y+1).0.)
• [Y] Does this PR change the the list of algorithms available -- either adding, removing, or renaming? Does this PR otherwise change an API? (If so, PRs in oqs-provider, OQS-OpenSSL, OQS-BoringSSL, and OQS-OpenSSH will also need to be ready for review and merge by the time this is merged.)

[baentsch]

This is the initial commit. The following commits should have more weighty code additions.

I'm not sure I like this approach: Are you saying you want to keep adding to a PR during development? This will generate loads of unnecessary notification emails to the whole team (which in turn will lead to all emails about your work to be disregarded); it further isn't particularly helpful (e.g., for auto-filtering out those emails) that this PR is not marked Draft.

My preference would be for a PR to be created in OQS only when it's basically done -- and to be marked Ready for Review only when its CI passes.

[ashman-p]

No worries, i get it. I most likely misunderstood the discussion concerning the initial commit of the LMS source and preferences on code sizes for reviews.

[xvzcf]

My preference would be for a PR to be created in OQS only when it's basically done -- and to be marked Ready for Review only when its CI passes.

Rather than having a single big PR, I think we should break this into several PRs such that each is a unit of work that can be merged in. We could discuss this further in the status meeting.