webui: support standalone facets in navigation module

One can access standard standalone facets with:
  `navigation.show('facet_name')`
and completely custom facets with low level call:
  `navigation.show_generic('/custom/hash', facet)``

Reviewed-By: Endi Sukma Dewata <edewata@redhat.com>

install/ui/src/freeipa/navigation.js

@@ -77,7 +77,7 @@ define([
          * type.
          *
          * When facet is defined as a string it has to be registered in
-         * facet register. //FIXME: not yet implemented
+         * facet register.
          *
          * When it's an object (Facet) and has an entity set it will be
          * dealt as entity facet.
@@ -98,9 +98,7 @@ define([
             var facet = params.facet;
 
             if (typeof facet === 'string') {
-                // FIXME: doesn't work at the moment
-                throw 'Not yet supported';
-                //facet = IPA.get_facet(facet);
+                nav.navigate_to_facet(facet, params.args);
             }
 
             if (!facet) throw 'Argument exception: missing facet';
@@ -140,6 +138,22 @@ define([
                                                 params.pkeys, params.args);
         },
 
+        /**
+         * Uses lower level access
+         *
+         * `experimental`
+         *
+         * Navigates to generic page by changing hash.
+         *
+         * @param  {string} hash Hash of the change
+         * @param  {Object} [facet] Facet we are navigating to. Usually used for
+         *                          notification purposes
+         */
+        show_generic: function(hash, facet) {
+            var nav = get_router();
+            nav.navigate_to_hash(hash, facet);
+        },
+
         /**
          * Show default facet
          * @method show_default