fix(package): update @angular/http to version 5.1.3

Closes #18

Author: greenkeeper[bot]

package.json

@@ -19,7 +19,7 @@
     "@angular/compiler": "^4.0.0",
     "@angular/core": "^4.0.0",
     "@angular/forms": "^4.0.0",
-    "@angular/http": "^4.0.0",
+    "@angular/http": "^5.1.3",
     "@angular/platform-browser": "^4.0.0",
     "@angular/platform-browser-dynamic": "^4.0.0",
     "@angular/router": "^4.0.0",