Web crypto support information for MS Edge (#2738)
Web crypto support information for MS Edge (#2738)

* Web crypto support information for MS Edge, based on:
  [MS-WEBCRYPTO] - Microsoft Edge Web Cryptography API Standards Support Document
  v20180828, Release: August 28, 2018
  https://msdn.microsoft.com/en-us/library/mt801187.aspx
Copyright © 2018 Microsoft Corporation

* Corrected placement of the worker_support section
Added "status" section and firefox.version_added to worker_support

* Move the Edge compatibility notes to their specific sub-items.

* Further clarification of Edge partial support.

mdn/browser-compat-data,chrisdavidmills/browser-compat-data,mdn/browser-compat-data,chrisdavidmills/browser-compat-data