[paymentrequest] Add registration explainer (#64)

You can view, comment on, or merge this pull request online at:

  https://github.com/WICG/paymentrequest/pull/64

-- Commit Summary --

  * Add rationale and reconfigure repo structure to make more sense by having explicit doc loation
  * Fix links and update text
  * Typing is hard - fix file names
  * Updates based on feedback
  * Broke images again - oops
  * Make location change known
  * first draft of registration explainer
  * formatting fixes
  * upstream
  * re-add typo fixes

-- File Changes --

    M docs/rationale.md (2)
    A docs/registration.md (218)

-- Patch Links --

https://github.com/WICG/paymentrequest/pull/64.patch
https://github.com/WICG/paymentrequest/pull/64.diff

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Reply to this email directly or view it on GitHub:
https://github.com/WICG/paymentrequest/pull/64