NSFS | NC | S3 flow support

[romayalon]

Explain the changes

1. create & delete bucket flows
2. put/set/delete bucket policy
3. set bucket versioning
4. put/set/delete bucket website - wasn't tested
5. put/set/delete bucket encryption - wasn't tested

Issues: Fixed #xxx / Gap #xxx

1. TODO: add automatic nc system tests

Testing Instructions:

currently just manual tests -

1. create account json under /path/to/config_dir/accounts/access_key.json
2. run nsfs nc - sudo node src/cmd/nsfs /path/to/fs/root_path --config_root=/path/to/config_dir/
3. alias s3-user='AWS_ACCESS_KEY_ID=access_key AWS_SECRET_ACCESS_KEY=secret_key aws --endpoint https://localhost:6443 --no-verify-ssl s3'
4. s3-user mb/ls/cp etc
5. s3-user api put-bucket-policy/put-bucket-versioning/delete-bucket etc

• Doc added/updated
• Tests added

[naveenpaul1]

LGTM