Login page before enter into Admin Dashboard

### Issue type
Unable to find lode for Login and Signup

**I'm submitting a ...** (check one with "x")

* [ ] bug report
* [ ] feature request
* [x] question about the decisions made in the repository

### Issue description
I can see the login under Auth in the dashboard, but not able to find the code code Login and Signup components. When i search, it is showing the code in mode_modules. I don't think we update that code.

**Current behavior:**

I can see the login page in the admin dashboard, but not as home page before we access the admin dashboard.

**Expected behavior:**

I would like to load the Login and Signup page before we give an access to the Dashboard. Once user signed in successfully, then we should redirect to the Dashboard. I have followed many articles, but didn't find the exact solution.

**Steps to reproduce:**

**Related code:**

```
insert short code snippets here
```

### Other information:

**npm, node, OS, Browser**
```

```
NPM - 6.4.1
Node - v10.15.1
Chrome - 72.0.3626.121
**Angular, Nebular**
```

```
ngx-admin - 2.0.0
Nebular - 3.1.0
Angular - 7.0.3