licensing: add list of whitelisted licenses

[nikhita]

This is a follow up of kubernetes/community#3231 and kubernetes/community#3239.

This PR adds the list of approved whitelisted licenses by the CNCF Governing Board, as per the slide deck shared by @swinslow. (Ref: kubernetes/steering#57 (comment))

/cc @swinslow @dims @justaugustus
members involved in the sig-release licensing subproject

/cc @thockin @cblecker @sttts @apelisse @BenTheElder @soltysh
dep-approvers

/hold
Even though @swinslow made changes to the doc in kubernetes/community#3239, I still want to make sure that this is explicitly lgtm'ed by him because it includes lots of legalese

/sig release
/area licensing

[nikhita]

Note to reviewer: This description comes from https://github.com/kubernetes/community/tree/master/sig-release#subprojects.

[nikhita]

I dropped the SIG Architecture mailing list from here because this is primarily a SIG Release subproject.

Depending on the question/concern, we can include SIG Arch in the email thread if needed.

[justaugustus]

/lgtm
/approve

I'll leave Steve to lift the hold.

@swinslow -- if everything looks good to you, lift the hold by typing /hold cancel on a line by itself.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: justaugustus, nikhita

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• licensing/OWNERS [justaugustus,nikhita]

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[swinslow]

LGTM! Thanks @nikhita!

/hold cancel