NavTree: Make it possible to configure where in nav tree plugins live (#55484)

* NewIA: Plugin nav config

* progress

* Progress

* Things are working

* Add monitoring node

* Add alerts and incidents

* added experiment with standalone page

* Refactoring by adding a type for navtree root

* First test working

* More tests

* more tests

* Progress on richer config and sorting

* Sort weight working

* Path config

* Improving logic for not including admin or cfg nodes, making it the last step so that enterprise can add admin nodes without having to worry about the section not existing

* fixed index routes

* removed file

* Fixes

* Fixing tests

* Fixing more tests and adding support for weight config

* Updates

* Remove unused fake

* More fixes

* Minor tweak

* Minor fix

* Can now control position using sortweight even when existing items have no sortweight

* Added tests for frontend standalone page logic

* more tests

* Remove unused fake and fixed lint issue

* Moving reading settings to navtree impl package

* remove nav_id setting prefix

* Remove old test file

* Fix trailing newline

* Fixed bug with adding nil node

* fixing lint issue

* remove some code we have to rethink

* move read settings to PrivideService and switch to util.SplitString

pkg/api/datasources_test.go

@@ -17,6 +17,7 @@ import (
 	"github.com/grafana/grafana/pkg/api/routing"
 	"github.com/grafana/grafana/pkg/components/simplejson"
 	"github.com/grafana/grafana/pkg/models"
+	"github.com/grafana/grafana/pkg/plugins"
 	ac "github.com/grafana/grafana/pkg/services/accesscontrol"
 	"github.com/grafana/grafana/pkg/services/datasources"
 	"github.com/grafana/grafana/pkg/services/datasources/permissions"
@@ -47,7 +48,7 @@ func TestDataSourcesProxy_userLoggedIn(t *testing.T) {
 		// handler func being tested
 		hs := &HTTPServer{
 			Cfg:         setting.NewCfg(),
-			pluginStore: &fakePluginStore{},
+			pluginStore: &plugins.FakePluginStore{},
 			DataSourcesService: &dataSourcesServiceMock{
 				expectedDatasources: ds,
 			},
@@ -71,7 +72,7 @@ func TestDataSourcesProxy_userLoggedIn(t *testing.T) {
 			// handler func being tested
 			hs := &HTTPServer{
 				Cfg:         setting.NewCfg(),
-				pluginStore: &fakePluginStore{},
+				pluginStore: &plugins.FakePluginStore{},
 			}
 			sc.handlerFunc = hs.DeleteDataSourceByName
 			sc.fakeReqWithParams("DELETE", sc.url, map[string]string{}).exec()