Update to Bootstrap 4 stable

Author: mprahl

package.json

@@ -21,8 +21,8 @@
     "@angular/platform-browser": "^5.0.0",
     "@angular/platform-browser-dynamic": "^5.0.0",
     "@angular/router": "^5.0.0",
-    "@ng-bootstrap/ng-bootstrap": "^1.0.0-beta.5",
-    "bootstrap": "^4.0.0-beta.2",
+    "@ng-bootstrap/ng-bootstrap": "^1.0.0",
+    "bootstrap": "^4.0.0",
     "core-js": "^2.4.1",
     "font-awesome": "^4.7.0",
     "ngx-infinite-scroll": "^0.6.1",