docs: move to docusaurus (#1984)

* new site start

* ci: test docusaurus

* we use npm

* Update site_tests.yml

* Update site_tests.yml

* Update site_tests.yml

* do not ignore package.json

* Update package-lock.json

* Create deploy.yml

* Update docusaurus.config.js

* update authors

* Update docusaurus.config.js

* Update deploy.yml

* remove blog posts

* Update README.md

* delete old docs

* Update .gitignore

* delete template images

* Create 2022-02-03-welcome.md

site/.gitignore

@@ -0,0 +1,20 @@
+# Dependencies
+/node_modules
+
+# Production
+/build
+
+# Generated files
+.docusaurus
+.cache-loader
+
+# Misc
+.DS_Store
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*