[browser-payment-api] Editorial and some clarifications (#37)

VISA, Mastercard etc are not good examples of payment method
identifiers as there will likely be many payment methods that support
these payment instruments
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/browser-payment-api/pull/37

-- Commit Summary --

  * Editorial and some clarifications

-- File Changes --

    A .gitignore (2)
    M specs/architecture.html (21)

-- Patch Links --

https://github.com/w3c/browser-payment-api/pull/37.patch
https://github.com/w3c/browser-payment-api/pull/37.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/browser-payment-api/pull/37