feat(handle error): add condition for server errors
feat(handle error): add condition for server errors

Ismaestro/angular2-tour-of-heroes,Ismaestro/angular4-example-app,Ismaestro/angular4-example-app,Ismaestro/angular2-tour-of-heroes,Ismaestro/angular4-example-app,Ismaestro/angular2-tour-of-heroes