Require thread library explicitly for 1.9.x Ruby versions

hartator · hartator · commit 9fc60b5385c8 · 2016-10-17T12:42:05.000-05:00
diff --git a/lib/wayback_machine_downloader.rb b/lib/wayback_machine_downloader.rb
@@ -1,5 +1,6 @@
 # encoding: UTF-8
 
+require 'thread'
 require 'net/http'
 require 'open-uri'
 require 'fileutils'
