Fix for issue #163

Update the regex used to find URLs to account for single quotes in the
pattern.

lib/jekyll/generators/queue_webmentions.rb

@@ -72,7 +72,7 @@ def get_mentioned_uris(post)
         if post.data["in_reply_to"]
           uris[post.data["in_reply_to"]] = false
         end
-        post.content.scan(/(?:https?:)?\/\/[^\s)#\[\]{}<>%|\^"]+/) do |match|
+        post.content.scan(/(?:https?:)?\/\/[^\s)#\[\]{}<>%|\^"']+/) do |match|
           unless uris.key? match
             uris[match] = false
           end