Logger and Configuration Refactoring (#573)

* Logging: Refactor log targets into Ryujinx.Common

* Logger: Implement JSON Log Target

* Logger: Optimize Console/File logging targets

Implement a simple ObjectPool to pool up StringBuilders to avoid causing excessive GCing of gen1/2 items when large amounts of log entries are being generated.

We can also pre-determine the async overflow action at initialization time, allowing for an easy optimization in the message enqueue function, avoiding a number of comparisons.

* Logger: Implement LogFormatters

* Config: Refactor configuration file and loading

* Config: Rename to .jsonc to avoid highlighting issues in VSC and GitHub

* Resolve style nits

* Config: Resolve incorrect default key binding

* Config: Also update key binding default in schema

* Tidy up namespace imports

* Config: Update CONFIG.md to reflect new Config file

Ryujinx.Common/Logging/Targets/JsonLogTarget.cs

@@ -0,0 +1,35 @@
+using System.IO;
+using Utf8Json;
+
+namespace Ryujinx.Common.Logging
+{
+    public class JsonLogTarget : ILogTarget
+    {
+        private Stream _stream;
+        private bool   _leaveOpen;
+
+        public JsonLogTarget(Stream stream)
+        {
+            _stream = stream;
+        }
+
+        public JsonLogTarget(Stream stream, bool leaveOpen)
+        {
+            _stream    = stream;
+            _leaveOpen = leaveOpen;
+        }
+
+        public void Log(object sender, LogEventArgs e)
+        {
+            JsonSerializer.Serialize(_stream, e);
+        }
+
+        public void Dispose()
+        {
+            if (!_leaveOpen)
+            {
+                _stream.Dispose();
+            }
+        }
+    }
+}