Generate an llms.txt file (#630)

Author: dbgrandi

Gemfile

@@ -9,6 +9,7 @@ source "https://rubygems.org"
 # This will help ensure the proper Jekyll version is running.
 # Happy Jekylling!
 gem "jekyll", "4.1.0"
+gem "jekyll-llmstxt"
 
 # This is the default theme for new Jekyll sites. You may change this to anything you like.
 # gem "minima", "~> 2.0"