@ngeth : add ProviderModule

app.module.ts

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { ProviderModule } from '@ngeth/provider';

import { AppComponent } from './app.component';

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    ProviderModule.init('https://ropsten.infura.io')
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }