Add debug docs

docs/.pages

@@ -4,4 +4,5 @@ arrange:
   - forms.md
   - context-lifetime.md
   - php-js-interoperability.md
+  - debugging.md
   - api-reference.md

docs/debugging.md

@@ -0,0 +1,11 @@
+# Debugging PHP in Blazor
+
+From now on, you can debug your PHP code running in the browser in Visual Studio ! You just run the *Blazor.Server* in `DEBUG` mode and set the breakpoint to any line of your PHP code. The **Peachpie.Blazor.Sdk** then sets the environment to enable PHP debugging.       
+
+![debug](E:\OwnCode\Github\peachpie-blazor\docs\images\debug.png)
+
+## Logging 
+
+Because `PhpComponent` and `PhpScriptProvider` have many stages, we provide helpful logs describing the behaviour of the components. Logs are displayed in the browser console by default. If you want to prohibit logging, just add `builder.Logging.SetMinimumLevel(LogLevel.None);` to *Program.cs* in **Blazor.Client** project.
+
+![logs](E:\OwnCode\Github\peachpie-blazor\docs\images\log.png)