Improve command documentation features

src/Discord.Net.Commands/Attributes/DescriptionAttribute.cs

@@ -2,6 +2,7 @@
 
 namespace Discord.Commands
 {
+    // Full summary of method/parameter
     [AttributeUsage(AttributeTargets.Method | AttributeTargets.Parameter)]
     public class DescriptionAttribute : Attribute
     {
@@ -12,7 +13,8 @@ namespace Discord.Commands
         }
     }
 
-    [AttributeUsage(AttributeTargets.Method)]
+    // Brief summary of method/module
+    [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class)]
     public class SynopsisAttribute : Attribute
     {
         public string Text { get; }

src/Discord.Net.Commands/Command.cs

@@ -103,7 +103,7 @@ namespace Discord.Commands
                     throw new InvalidOperationException("Remainder parameters must be the last parameter in a command.");
 
                 string name = parameter.Name;
-                string description = typeInfo.GetCustomAttribute<DescriptionAttribute>()?.Text;
+                string description = parameter.GetCustomAttribute<DescriptionAttribute>()?.Text;
                 bool isOptional = parameter.IsOptional;
                 object defaultValue = parameter.HasDefaultValue ? parameter.DefaultValue : null;
 

src/Discord.Net.Commands/Module.cs

@@ -9,6 +9,7 @@ namespace Discord.Commands
     {
         public CommandService Service { get; }
         public string Name { get; }
+        public string Synopsis { get; }
         public IEnumerable<Command> Commands { get; }
         internal object Instance { get; }
 
@@ -18,6 +19,10 @@ namespace Discord.Commands
             Name = typeInfo.Name;
             Instance = instance;
 
+            var synopsisAttr = typeInfo.GetCustomAttribute<SynopsisAttribute>();
+            if (synopsisAttr != null)
+                Synopsis = synopsisAttr.Text;
+
             List<Command> commands = new List<Command>();
             SearchClass(instance, commands, typeInfo, moduleAttr.Prefix ?? "");
             Commands = commands;