Guides for Serilog and EFCore (#2134)

* Add serilog guide

* added suggestions from Rozen

* Add efcore guide

* Fix review changes

* Fix grammatical errors & review points

docs/guides/other_libs/samples/ConfiguringSerilog.cs

@@ -0,0 +1,36 @@
+using Discord;
+using Serilog;
+using Serilog.Events;
+
+public class Program
+{
+    static void Main(string[] args) => new Program().MainAsync().GetAwaiter().GetResult();
+
+    public async Task MainAsync()
+    {
+        Log.Logger = new LoggerConfiguration()
+            .MinimumLevel.Verbose()
+            .Enrich.FromLogContext()
+            .WriteTo.Console()
+            .CreateLogger();
+
+        _client = new DiscordSocketClient();
+
+        _client.Log += LogAsync;
+
+        //  You can assign your bot token to a string, and pass that in to connect.
+        //  This is, however, insecure, particularly if you plan to have your code hosted in a public repository.
+        var token = "token";
+
+        // Some alternative options would be to keep your token in an Environment Variable or a standalone file.
+        // var token = Environment.GetEnvironmentVariable("NameOfYourEnvironmentVariable");
+        // var token = File.ReadAllText("token.txt");
+        // var token = JsonConvert.DeserializeObject<AConfigurationClass>(File.ReadAllText("config.json")).Token;
+
+        await _client.LoginAsync(TokenType.Bot, token);
+        await _client.StartAsync();
+
+        // Block this task until the program is closed.
+        await Task.Delay(Timeout.Infinite);
+    }
+}