[w3c/webauthn] ca1f0e: Allow callers to explicitly specify RP ID (#198)

  Branch: refs/heads/master
  Home:   https://github.com/w3c/webauthn
  Commit: ca1f0ee7a224cd089e21ba7e5a0c530723e8ca2f
      https://github.com/w3c/webauthn/commit/ca1f0ee7a224cd089e21ba7e5a0c530723e8ca2f
  Author: Vijay Bharadwaj <vijaybh@users.noreply.github.com>
  Date:   2016-09-28 (Wed, 28 Sep 2016)

  Changed paths:
    M index.bs

  Log Message:
  -----------
  Allow callers to explicitly specify RP ID (#198)

* 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.

* Remove rpId from ClientData

Since rpId is now equal to origin except when explicitly specified by
the caller, and it is folded into the authenticatorData, having it in
ClientData adds no value.

Fixes #189

* Incorporate feedback from @equalsJeffH

* More feedback from @equalsJeffH

* Incorporate feedback from @equalsJeffH

Note this PR also fixes #178 by removing all use of the term lowercase