Aded more documentation to the readme (#14)

Author: abergs

README.md

@@ -33,6 +33,84 @@ From within Visual Studio:
 5. Click on the Passwordless package, select the appropriate version in the
    right-tab and click *Install*.
 
+
+## Getting started
+
+Follow the [Get started guide](https://docs.passwordless.dev/guide/get-started.html)
+
+#### Register to Dependency Injection
+
+```csharp
+
+// in Program.cs or Startup.cs
+services.AddPasswordlessSdk(options =>
+{
+   options.ApiSecret = "your_api_secret";
+});
+
+```
+### Register a passkey
+
+```csharp
+
+[HttpGet("/create-token")]
+public async Task<IActionResult> GetRegisterToken(string alias)
+{
+
+   // Get existing userid from session or create a new user in your database
+   var userId = Guid.NewGuid().ToString();
+
+   // Options to give the Api
+   var payload = new RegisterOptions
+   {
+      UserId = userId, // your user id
+      Username = alias, // e.g. user email, is shown in browser ui
+      Aliases = new HashSet<string> { alias } // Optional: Link this userid to an alias (e.g. email)
+   };
+
+   try
+   {
+      var token = await _passwordlessClient.CreateRegisterTokenAsync(payload);
+
+      // return this token to the frontend
+      return Ok(token);
+   }
+   catch (PasswordlessApiException e)
+   {
+      return new JsonResult(e.Details)
+      {
+            StatusCode = (int)e.StatusCode,
+      };
+   }
+}
+
+```
+
+### Verify user
+
+```csharp
+[HttpGet]
+[Route("/verify-signin")]
+public async Task<IActionResult> VerifySignInToken(string token)
+{
+   try
+   {
+      var verifiedUser = await _passwordlessClient.VerifyTokenAsync(token);
+      // Sign the user in, set a cookie, etc,
+      return Ok(verifiedUser);
+   }
+   catch (PasswordlessApiException e)
+   {
+      return new JsonResult(e.Details)
+      {
+            StatusCode = (int)e.StatusCode
+      };
+   }
+}
+```
+
+
+
 ## Documentation
 
 For a comprehensive list of examples, check out the [API