message: fix reference to facebook in twilio doc
diff: @@ -105,9 +105,9 @@ controller.on('message', async(bot, message) {
  ## Botkit Extensions
  -In Botkit handlers, the `bot` worker for Facebook contains [all of the base methods](../docs/reference/core.md#BotWorker) as well as the following platform-specific extensions:
  +In Botkit handlers, the `bot` worker for Twilio contains [all of the base methods](../docs/reference/core.md#BotWorker) as well as the following platform-specific extensions:
  -### [bot.startConversationWithUser()](../docs/reference/twilio-sms#startconversationwithuser)
  +### [bot.startConversationWithUser()](../docs/reference/twilio-sms.md#startconversationwithuser)
  Use this method to initiate a conversation with a user. After calling this method, any further actions carried out by the bot worker will happen with the specified user.
  