UI ember engines (#6718)

Adds replication engine and core in-repo addon

ui/lib/core/addon/components/doc-link.js

@@ -0,0 +1,33 @@
+import Component from '@ember/component';
+import { computed } from '@ember/object';
+import hbs from 'htmlbars-inline-precompile';
+
+/**
+ * @module DocLink
+ * `DocLink` components are used to render anchor links to relevant Vault documentation.
+ *
+ * @example
+ * ```js
+    <DocLink @path="/docs/secrets/kv/kv-v2.html">Learn about KV v2</DocLink>
+ * ```
+ *
+ * @param path="/"{String} - The path to documentation on vaultproject.io that the component should link to.
+ *
+ */
+
+export default Component.extend({
+  tagName: 'a',
+  classNames: ['doc-link'],
+  attributeBindings: ['target', 'rel', 'href'],
+
+  layout: hbs`{{yield}}`,
+
+  target: '_blank',
+  rel: 'noreferrer noopener',
+  host: 'https://www.vaultproject.io',
+
+  path: '/',
+  href: computed('host', 'path', function() {
+    return `${this.host}${this.path}`;
+  }),
+});