Changes for move to Netlify (#4464)

* disable jekyll-redirect-from gem

* add _redirects file

* disable 404 redirect script

* add 301 redirect to test

* retain _redirects file

* Convert redirect_from's to _redirect file. (#4409)

* Remove redirect_from's. (#4424)

* Add 301's to _redirects. (#4427)

* add whitespace before 301

* move redirects in /js/redirects/js to _redirects

* add disabled option for cn redirect

* convert include to array in _config.yml

* enable redirects.js script for legacy support

docs/concepts/cluster-administration/network-plugins.md

@@ -4,9 +4,6 @@ assignees:
 - freehan
 - thockin
 title: Network Plugins
-redirect_from:
-- "/docs/admin/network-plugins/"
-- "/docs/admin/network-plugins.html"
 ---
 
 * TOC