Kubernetes 1.8 reference docs (#5632)

* Kubernetes 1.8 reference docs

* Kubectl reference docs for 1.8

* Update side bar with 1.8 kubectl and api ref docs links

docs/api-reference/v1.8/node_modules/mime/build/build.js

@@ -0,0 +1,11 @@
+var db = require('mime-db');
+
+var mapByType = {};
+Object.keys(db).forEach(function(key) {
+  var extensions = db[key].extensions;
+  if (extensions) {
+    mapByType[key] = extensions;
+  }
+});
+
+console.log(JSON.stringify(mapByType));