add pages for uploading and help

pdb-js/src/app/app-routing.module.ts

@@ -1,11 +1,27 @@
 import { NgModule } from '@angular/core';
 import { Routes, RouterModule } from '@angular/router';
+import { VisualizationPageComponent } from './visualization-page/visualization-page.component';
+import { MainPageComponent } from './main-page/main-page.component';
+import { UploadPageComponent } from './upload-page/upload-page.component';
+import { HelpPageComponent } from './help-page/help-page.component';
 
 
-const routes: Routes = [];
+const routes: Routes = [
+  { path: '', component: MainPageComponent},
+  { path: 'vis', component: VisualizationPageComponent },
+  { path: 'upload', component: UploadPageComponent },
+  { path: 'help', component: HelpPageComponent },
+ // { path: '**', component: PageNotFoundComponent }
+];
 
 @NgModule({
-  imports: [RouterModule.forRoot(routes)],
+  imports: [
+    RouterModule.forRoot(
+      routes,
+      //{ enableTracing: true } // <-- debugging purposes only
+    )
+  ],
+  declarations: [VisualizationPageComponent],
   exports: [RouterModule]
 })
 export class AppRoutingModule { }