[w3c/webauthn] 644551: Incorporate feedback from JeffH, part 1

  Branch: refs/heads/vgb-refine-makecredential
  Home:   https://github.com/w3c/webauthn
  Commit: 64455164f7881d198d8a9d14534a3107e6feca54
      https://github.com/w3c/webauthn/commit/64455164f7881d198d8a9d14534a3107e6feca54
  Author: Vijay Bharadwaj <vijaybh@users.noreply.github.com>
  Date:   2017-03-02 (Thu, 02 Mar 2017)

  Changed paths:
    M index.bs

  Log Message:
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  Incorporate feedback from JeffH, part 1