added download only mode that simply downloads files to the client when the server finishes the download

added dependency on savefile library for download-only mode

package.json

@@ -25,6 +25,7 @@
     "@angular/platform-browser-dynamic": "^8.2.11",
     "@angular/router": "^8.2.11",
     "core-js": "^2.4.1",
+    "file-saver": "^2.0.2",
     "ng4-configure": "^0.1.7",
     "rxjs": "^6.5.3",
     "rxjs-compat": "^6.0.0-rc.0",
@@ -32,10 +33,11 @@
     "zone.js": "~0.9.1"
   },
   "devDependencies": {
-    "@angular-devkit/build-angular": "~0.803.12",
+    "@angular-devkit/build-angular": "^0.803.24",
     "@angular/cli": "^8.3.12",
     "@angular/compiler-cli": "^8.2.11",
     "@angular/language-service": "^8.2.11",
+    "@types/file-saver": "^2.0.1",
     "@types/jasmine": "2.5.45",
     "@types/node": "~6.0.60",
     "codelyzer": "^5.0.1",