Will be nice to clear auth credentials. For example, I'm using a proxy that accepts options via username:

```
proxy.com:8080
user: wiliam_country_US
```

So, if I want to change the peer node, I change my username:

```
proxy.com:8080
user: wiliam_country_GB
```

But, I'm not changing the proxy, so electron has valid credentials and is not going to trigger `login` event.

I'm searching the way to clean auth settings so electron asks them again.
atom/browser/api/atom_api_session.cc
const net::ProxyConfig& config,
                  const base::Closure& callback) {
  auto proxy_service = getter->GetURLRequestContext()->proxy_service();
  proxy_service->ResetConfigService(base::WrapUnique(
      new net::ProxyConfigServiceFixed(config)));
  
  proxy_service->ForceReloadProxyConfig();
  RunCallbackInUI(callback);
}
void SetCertVerifyProcInIO(
    const scoped_refptr<net::URLRequestContextGetter>& context_getter,
    const AtomCertVerifier::VerifyProc& proc) {
  auto request_context = context_getter->GetURLRequestContext();
  static_cast<AtomCertVerifier*>(request_context->cert_verifier())->
      SetVerifyProc(proc);
}
void ClearHostResolverCacheInIO(