Refactor command system

PluralKit.Bot/CommandSystem/Command.cs

@@ -0,0 +1,16 @@
+namespace PluralKit.Bot.CommandSystem
+{
+    public class Command
+    {
+        public string Key { get; }
+        public string Usage { get; }
+        public string Description { get; }
+        
+        public Command(string key, string usage, string description)
+        {
+            Key = key;
+            Usage = usage;
+            Description = description;
+        }
+    }
+}