[webauthn] new commits pushed by selfissued

The following commits were just pushed by selfissued to https://github.com/w3c/webauthn:

* Shortened selection and attachment identifiers sent over the wire
  by Mike Jones
https://github.com/w3c/webauthn/commit/479b4befa33f4b2f973ab06c22291a765e527cb7

Received on Wednesday, 2 August 2017 20:41:12 UTC