Add site function

Fixes #1324

content/en/functions/site.md

@@ -0,0 +1,26 @@
+---
+title: site
+linktitle: site
+description: The `site` function provides global access the same data as `.Site` page method
+godocref:
+date: 2021-02-11
+publishdate: 2021-02-11
+lastmod: 2021-02-11
+keywords: []
+categories: [functions]
+menu:
+  docs:
+    parent: "functions"
+toc:
+signature: ["site"]
+workson: []
+hugoversion:
+relatedfuncs: ["hugo"]
+deprecated: false
+draft: false
+aliases: []
+---
+
+`site` is a global function which returns the same data as the `.Site` page method. See: [Site Variables]({{< relref "/variables/site" >}}).
+
+