Code cleanup; Reader classes renamed to Decoders, Writers to Encoders, every Decoder must have a corresponding Settings class now just like Encoders. UserDefinedEncoders renamed to CommandLineEncoders, etc.

CUETools.Codecs.libmp3lame/LameWriterVBRSettings.cs

@@ -0,0 +1,34 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Text;
+using Newtonsoft.Json;
+
+namespace CUETools.Codecs.libmp3lame
+{
+    [JsonObject(MemberSerialization.OptIn)]
+    public class VBREncoderSettings : LameEncoderSettings
+    {
+        public override string Extension => "mp3";
+
+        public override string Name => "libmp3lame-VBR";
+
+        public override int Priority => 2;
+
+        [JsonProperty]
+        [DefaultValue(LameQuality.High)]
+        public LameQuality Quality { get; set; }
+
+        public VBREncoderSettings()
+            : base("V9 V8 V7 V6 V5 V4 V3 V2 V1 V0", "V2")
+        {
+        }
+    
+        public override void Apply(IntPtr lame)
+        {
+            libmp3lamedll.lame_set_VBR(lame, (int)LameVbrMode.Default);
+            libmp3lamedll.lame_set_VBR_quality(lame, 9 - this.EncoderModeIndex);
+            libmp3lamedll.lame_set_quality(lame, (int)this.Quality);
+        }
+    }
+}