Chore: Automate Setting New UUID's When Running the Seeds Task

Because:
* It is frustrating and time consuming having to manually generate uuids and then copy and paste them into the seed files.
* To get a random uuid automatically created for you, you just need to give any identifier_uuid attribute the value of "create_uuid" and then run the seeds as normal.

This commit.
* Adds a seed_uuids generator which will look for any "create_uuid" strings within the fixtures files and replace any instances with a new random uuid.
* New generator can be invoked form the command line manually with `bin/rails g seed_uuids`.
* Generator is invoked during the seed task everything is done with one command instead of needing to manually run the uuid generator first and then and then the seeds task.

db/seeds.rb

@@ -10,6 +10,7 @@
 load './db/fixtures/lessons/node_js_lessons.rb'
 load './db/fixtures/lessons/git_lessons.rb'
 
+Rails::Generators.invoke('seed_uuids') if Rails.env.development?
 SeedFu.seed
 
 # GENERATE SUCCESS STORY Content

lib/generators/rails/seed_uuids/USAGE

@@ -0,0 +1,5 @@
+Description:
+bin/rails generate seed_uuids
+
+This will replace "create_uuid" in the seeds file with a real uuid
+

lib/generators/rails/seed_uuids/seed_uuids_generator.rb

@@ -0,0 +1,9 @@
+class Rails::SeedUuidsGenerator < Rails::Generators::Base
+  def generate_uuids
+    seed_files = Dir.glob('db/fixtures/**/*').reject { |f| File.directory?(f) }
+
+    seed_files.each do |file_name|
+      gsub_file(file_name, 'create_uuid', SecureRandom.uuid)
+    end
+  end
+end