Proposal to remove governance docs and refer to those in org-wide repo .github

[yizha1]

.github repo is now the organization-wide repository for common governance documents. The following governance documents have been copied to .github repo by PR notaryproject/.github#17, and will be continously maintained in .github repo.

• https://github.com/notaryproject/notary/blob/master/GOVERNANCE.md
• https://github.com/notaryproject/notary/blob/master/CODE_OF_CONDUCT.md
• https://github.com/notaryproject/notary/blob/master/CONTRIBUTING.md
• https://github.com/notaryproject/notary/blob/master/PROJECTS

So, the proposal is to remove the above documents from notary repo.

cc @toddysm

[FeynmanZhou]

LGTM

[toddysm]

Tagging @HuKeping, @justincormack, @SteveLasker, and @NiazFK for decision on this one

[priteshbandi]

LGTM