Some slight README organization tweaks

Author: nblumhardt

README.md

@@ -82,7 +82,7 @@ That's it! With the level bumped up a little you will see log output resembling:
 
 A more complete example, showing `appsettings.json` configuration, can be found in [the sample project here](https://github.com/serilog/serilog-aspnetcore/tree/dev/samples/EarlyInitializationSample).
 
-### Request logging <sup>`3.0.0-*`</sup>
+### Request logging <sup>`3.0.0`</sup>
 
 The package includes middleware for smarter HTTP request logging. The default request logging implemented by ASP.NET Core is noisy, with multiple events emitted per request. The included middleware condenses these into a single event that carries method, path, status code, and timing information.
 
@@ -134,7 +134,7 @@ Then, in your application's _Startup.cs_, add the middleware with `UseSerilogReq
             // Other app configuration
 ```
 
-It's important that the `UseSerilogRequestLogging()` call appears _before_ handlers such as MVC. The middleware will not time or log components that appear before it in the pipeline. You can override the message template by specifying `messageTemplate`. (This can be utilized to exclude noisy handlers from logging, such as `UseStaticFiles()`, by placing `UseSerilogRequestLogging()` after them.)
+It's important that the `UseSerilogRequestLogging()` call appears _before_ handlers such as MVC. The middleware will not time or log components that appear before it in the pipeline. (This can be utilized to exclude noisy handlers from logging, such as `UseStaticFiles()`, by placing `UseSerilogRequestLogging()` after them.)
 
 During request processing, additional properties can be attached to the completion event using `IDiagnosticContext.Set()`:
 
@@ -159,18 +159,25 @@ During request processing, additional properties can be attached to the completi
 
 This pattern has the advantage of reducing the number of log events that need to be constructed, transmitted, and stored per HTTP request. Having many properties on the same event can also make correlation of request details and other data easier.
 
-The following request information will be added as log properties:
+The following request information will be added as properties by default:
 
 * `RequestMethod`
 * `RequestPath`
 * `StatusCode`
 * `Elapsed`
 
-Not enough? You can extend the information that is being emitted by using `options.EnrichDiagnosticContext`:
+You can modify the message template used for request completion events, add additional properties, or change the event level, using the `options` callback on `UseSerilogRequestLogging()`:
 
 ```csharp
 app.UseSerilogRequestLogging(options =>
 {
+    // Customize the message template
+    options.MessageTemplate = "Handled {RequestPath}";
+    
+    // Emit debug-level events instead of the defaults
+    options.GetLevel = (httpContext, elapsed, ex) => LogEventLevel.Debug;
+    
+    // Attach additional properties to the request completion event
     options.EnrichDiagnosticContext = (diagnosticContext, httpContext) =>
     {
         diagnosticContext.Set("RequestHost", httpContext.Request.Host.Value);