Apply consistency to attributes in the commands extension

This resolves #527.

Not sure if I missed any, putting this up for review.

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

@@ -3,7 +3,7 @@ using System;
 namespace Discord.Commands
 {
     /// <summary> Provides aliases for a command. </summary>
-    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
+    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = false, Inherited = true)]
     public class AliasAttribute : Attribute
     {
         /// <summary> The aliases which have been defined for the command. </summary>

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

@@ -1,8 +1,8 @@
-using System;
+using System;
 
 namespace Discord.Commands
 {
-    [AttributeUsage(AttributeTargets.Method)]
+    [AttributeUsage(AttributeTargets.Method, AllowMultiple = false, Inherited = true)]
     public class CommandAttribute : Attribute
     {
         public string Text { get; }

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

@@ -1,8 +1,8 @@
-using System;
+using System;
 
 namespace Discord.Commands
 {
-    [AttributeUsage(AttributeTargets.Class)]
+    [AttributeUsage(AttributeTargets.Class, AllowMultiple = false, Inherited = true)]
     public class DontAutoLoadAttribute : Attribute
     {
     }

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

@@ -2,7 +2,7 @@ using System;
 
 namespace Discord.Commands {
 
-  [AttributeUsage(AttributeTargets.Property)]
+  [AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)]
   public class DontInjectAttribute : Attribute {
   }
 

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

@@ -1,8 +1,8 @@
-using System;
+using System;
 
 namespace Discord.Commands
 {
-    [AttributeUsage(AttributeTargets.Class)]
+    [AttributeUsage(AttributeTargets.Class, AllowMultiple = false, Inherited = true)]
     public class GroupAttribute : Attribute
     {
         public string Prefix { get; }

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

@@ -3,7 +3,7 @@ using System;
 namespace Discord.Commands
 {
     // Override public name of command/module
-    [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class | AttributeTargets.Parameter)]
+    [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class | AttributeTargets.Parameter, AllowMultiple = false, Inherited = true)]
     public class NameAttribute : Attribute
     {
         public string Text { get; }

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

@@ -4,7 +4,7 @@ using System.Reflection;
 
 namespace Discord.Commands
 {
-    [AttributeUsage(AttributeTargets.Parameter)]
+    [AttributeUsage(AttributeTargets.Parameter, AllowMultiple = false, Inherited = true)]
     public class OverrideTypeReaderAttribute : Attribute
     {
         private static readonly TypeInfo _typeReaderTypeInfo = typeof(TypeReader).GetTypeInfo();
@@ -19,4 +19,4 @@ namespace Discord.Commands
             TypeReader = overridenTypeReader;
         }
     } 
-}
+}

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

@@ -1,6 +1,5 @@
 using System;
 using System.Threading.Tasks;
-using Microsoft.Extensions.DependencyInjection;
 
 namespace Discord.Commands
 {
@@ -9,4 +8,4 @@ namespace Discord.Commands
     {
         public abstract Task<PreconditionResult> CheckPermissionsAsync(ICommandContext context, ParameterInfo parameter, object value, IServiceProvider services);
     }
-}
+}

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

@@ -3,7 +3,7 @@ using System;
 namespace Discord.Commands
 {
     /// <summary> Sets priority of commands </summary>
-    [AttributeUsage(AttributeTargets.Method)]
+    [AttributeUsage(AttributeTargets.Method, AllowMultiple = false, Inherited = true)]
     public class PriorityAttribute : Attribute
     {
         /// <summary> The priority which has been set for the command </summary>

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

@@ -1,8 +1,8 @@
-using System;
+using System;
 
 namespace Discord.Commands
 {
-    [AttributeUsage(AttributeTargets.Parameter)]
+    [AttributeUsage(AttributeTargets.Parameter, AllowMultiple = false, Inherited = true)]
     public class RemainderAttribute : Attribute
     {
     }

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

@@ -1,9 +1,9 @@
-using System;
+using System;
 
 namespace Discord.Commands
 {
     // Extension of the Cosmetic Summary, for Groups, Commands, and Parameters
-    [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class)]
+    [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class, AllowMultiple = false, Inherited = true)]
     public class RemarksAttribute : Attribute
     {
         public string Text { get; }

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

@@ -1,9 +1,9 @@
-using System;
+using System;
 
 namespace Discord.Commands
 {
     // Cosmetic Summary, for Groups and Commands
-    [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class | AttributeTargets.Parameter)]
+    [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class | AttributeTargets.Parameter, AllowMultiple = false, Inherited = true)]
     public class SummaryAttribute : Attribute
     {
         public string Text { get; }