[GRASS-git] [OSGeo/grass-website] b5c7b7: Update link to osgeo4w

[Paulo van Breugel]

  Branch: refs/heads/ecodiv-patch-1
  Home:   https://github.com/OSGeo/grass-website
  Commit: b5c7b72caed603a1971b7655e2dc4b1a102d12ad
      https://github.com/OSGeo/grass-website/commit/b5c7b72caed603a1971b7655e2dc4b1a102d12ad
  Author: Paulo van Breugel <paulo at ecodiv.org>
  Date:   2021-09-03 (Fri, 03 Sep 2021)

  Changed paths:
    M content/download/windows.en.md

  Log Message:
  -----------
  Update link to osgeo4w

Update of link to OSGeo4W, version 2. Include link to old version v1 + warning for existing users that they need a fresh install when migrating to version 2 (based on message on QGIS page)