Add Command and module instance parameters to CheckPermissions

After a small discussion with Joe4evr on discord, a way of retrieving the
state of a module appeared to be needed. The new override should provide
enough context to a bot dev to allow them to do what they want.

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

@@ -8,6 +8,6 @@ namespace Discord.Commands
     [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class, AllowMultiple = true, Inherited = true)]
     public abstract class PreconditionAttribute : Attribute
     {
-        public abstract Task<PreconditionResult> CheckPermissions(IMessage context);
+        public abstract Task<PreconditionResult> CheckPermissions(IMessage context, Command executingCommand, object moduleInstance);
     }
 }

src/Discord.Net.Commands/Attributes/Preconditions/RequireDMAttribute.cs

@@ -8,7 +8,7 @@ namespace Discord.Commands
     [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = false, Inherited = true)]
     public class RequireDMAttribute : PreconditionAttribute
     {
-        public override Task<PreconditionResult> CheckPermissions(IMessage context)
+        public override Task<PreconditionResult> CheckPermissions(IMessage context, Command executingCommand, object moduleInstance)
         {
             if (context.Channel is IGuildChannel)
                 return Task.FromResult(PreconditionResult.FromError("Command must be used in a DM"));

src/Discord.Net.Commands/Attributes/Preconditions/RequireGuildAttribute.cs

@@ -8,7 +8,7 @@ namespace Discord.Commands
     [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = false, Inherited = true)]
     public class RequireGuildAttribute : PreconditionAttribute
     {
-        public override Task<PreconditionResult> CheckPermissions(IMessage context)
+        public override Task<PreconditionResult> CheckPermissions(IMessage context, Command executingCommand, object moduleInstance)
         {
             if (!(context.Channel is IGuildChannel))
                 return Task.FromResult(PreconditionResult.FromError("Command must be used in a guild"));

src/Discord.Net.Commands/Attributes/Preconditions/RequirePermission.cs

@@ -23,9 +23,9 @@ namespace Discord.Commands.Attributes.Preconditions
             GuildPermission = null;
         }
 
-        public override async Task<PreconditionResult> CheckPermissions(IMessage context)
+        public override async Task<PreconditionResult> CheckPermissions(IMessage context, Command executingCommand, object moduleInstance)
         {
-            var result = await base.CheckPermissions(context).ConfigureAwait(false);
+            var result = await base.CheckPermissions(context, executingCommand, moduleInstance).ConfigureAwait(false);
 
             if (!result.IsSuccess)
                 return result;

src/Discord.Net.Commands/Attributes/Preconditions/RequireRoleAttribute.cs

@@ -23,9 +23,9 @@ namespace Discord.Commands
             Comparer = comparer;
         }
 
-        public override async Task<PreconditionResult> CheckPermissions(IMessage context)
+        public override async Task<PreconditionResult> CheckPermissions(IMessage context, Command executingCommand, object moduleInstance)
         {
-            var result = await base.CheckPermissions(context).ConfigureAwait(false);
+            var result = await base.CheckPermissions(context, executingCommand, moduleInstance).ConfigureAwait(false);
 
             if (!result.IsSuccess)
                 return result;

src/Discord.Net.Commands/Command.cs

@@ -46,14 +46,14 @@ namespace Discord.Commands
         {
             foreach (PreconditionAttribute precondition in Module.Preconditions)
             {
-                var result = await precondition.CheckPermissions(context).ConfigureAwait(false);
+                var result = await precondition.CheckPermissions(context, this, Module.Instance).ConfigureAwait(false);
                 if (!result.IsSuccess)
                     return result;
             }
 
             foreach (PreconditionAttribute precondition in Preconditions)
             {
-                var result = await precondition.CheckPermissions(context).ConfigureAwait(false);
+                var result = await precondition.CheckPermissions(context, this, Module.Instance).ConfigureAwait(false);
                 if (!result.IsSuccess)
                     return result;
             }