- removed ts-helper duplicate from package.json

- added npm update to .travis.yml file in case the version is too old

Author: madoar

.travis.yml

@@ -7,3 +7,6 @@ node_js:
   - "7"
   - "6"
   - "4"
+
+before_install: if [[ `npm -v` != 3* || `npm -v` != 4* ]]; then npm i -g npm@3; fi
+

package.json

@@ -42,7 +42,7 @@
     "@angular/router": "^3.3.1",
     "core-js": "^2.4.1",
     "rxjs": "^5.0.1",
-    "ts-helpers": "^1.1.1",
+    "ts-helpers": "^1.1.2",
     "zone.js": "^0.7.2"
   },
   "devDependencies": {
@@ -92,7 +92,6 @@
     "sass-loader": "^4.0.0",
     "style-loader": "^0.13.0",
     "to-string-loader": "^1.1.5",
-    "ts-helpers": "^1.1.2",
     "tslint": "^4.4.2",
     "tslint-loader": "^3.3.0",
     "typescript": "2.1.5",