[w3c/webauthn] 443482: Allow caller to explicitly specify its claimed RP ...

  Branch: refs/heads/vgb-explicit-rpid
  Home:   https://github.com/w3c/webauthn
  Commit: 443482ebdef447bd9fbeb8a5ce1b01d09feea0ac
      https://github.com/w3c/webauthn/commit/443482ebdef447bd9fbeb8a5ce1b01d09feea0ac
  Author: Vijay Bharadwaj <vijaybh@users.noreply.github.com>
  Date:   2016-09-13 (Tue, 13 Sep 2016)

  Changed paths:
    M index.bs

  Log Message:
  -----------
  Allow caller to explicitly specify its claimed RP ID

Alternative to #162 as suggested by @balfanz. This change also gets rid
of references to PSL and eTLD+1, replacing them with references to the
HTML specification instead.