[w3c/webpayments-methods-card] Add privacy and security section (#8)

Proposal to address https://github.com/w3c/webpayments-methods-card/issues/2

This is based on [Ian's PR](https://github.com/w3c/webpayments-methods-card/pull/7), but expands on the motivation for not storing credit card numbers. It also updates the call flow diagram to eliminate the suggestion that credit card numbers should be stored.
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/webpayments-methods-card/pull/8

-- Commit Summary --

  * Copy from webpayments-flows repo
  * Pointing diagram at this repository
  * Remove suggestion to store card
  * Add security and privacy considerations section

-- File Changes --

    A MerchantHosted-CardPayment-TargetWithSimpleApp.pml (100)
    M index.html (26)

-- Patch Links --

https://github.com/w3c/webpayments-methods-card/pull/8.patch
https://github.com/w3c/webpayments-methods-card/pull/8.diff

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/w3c/webpayments-methods-card/pull/8