PLT-7: Refactoring models to use translations (chunk 6)

- Add spanish translations

model/incoming_webhook.go

@@ -76,27 +76,27 @@ func IncomingWebhookListFromJson(data io.Reader) []*IncomingWebhook {
 func (o *IncomingWebhook) IsValid() *AppError {
 
 	if len(o.Id) != 26 {
-		return NewAppError("IncomingWebhook.IsValid", "Invalid Id", "")
+		return NewLocAppError("IncomingWebhook.IsValid", "model.incoming_hook.id.app_error", nil, "")
 	}
 
 	if o.CreateAt == 0 {
-		return NewAppError("IncomingWebhook.IsValid", "Create at must be a valid time", "id="+o.Id)
+		return NewLocAppError("IncomingWebhook.IsValid", "model.incoming_hook.create_at.app_error", nil, "id="+o.Id)
 	}
 
 	if o.UpdateAt == 0 {
-		return NewAppError("IncomingWebhook.IsValid", "Update at must be a valid time", "id="+o.Id)
+		return NewLocAppError("IncomingWebhook.IsValid", "model.incoming_hook.update_at.app_error", nil, "id="+o.Id)
 	}
 
 	if len(o.UserId) != 26 {
-		return NewAppError("IncomingWebhook.IsValid", "Invalid user id", "")
+		return NewLocAppError("IncomingWebhook.IsValid", "model.incoming_hook.user_id.app_error", nil, "")
 	}
 
 	if len(o.ChannelId) != 26 {
-		return NewAppError("IncomingWebhook.IsValid", "Invalid channel id", "")
+		return NewLocAppError("IncomingWebhook.IsValid", "model.incoming_hook.channel_id.app_error", nil, "")
 	}
 
 	if len(o.TeamId) != 26 {
-		return NewAppError("IncomingWebhook.IsValid", "Invalid channel id", "")
+		return NewLocAppError("IncomingWebhook.IsValid", "model.incoming_hook.team_id.app_error", nil, "")
 	}
 
 	return nil