Rename Module -> Plugin with basic find/replace

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

lib/contrib/linkbot.ex

@@ -1,5 +1,5 @@
 defmodule Omnibot.Contrib.Linkbot do
-  use Omnibot.Module
+  use Omnibot.Plugin
   require Logger
 
   @default_config timeout: 30_000
@@ -19,9 +19,6 @@ defmodule Omnibot.Contrib.Linkbot do
     plug Tesla.Middleware.FollowRedirects, max_redirects: 10
     plug Tesla.Middleware.Compression, format: "gzip"
 
-
-    @title_regex ~r"<title>(?<title>.+)</title>"i
-
     def get_title(url) do
       # 1. check for "meta" tag (in the header) with a "property" attribute of "og:title", and fetch the "content" attribute of that tag
       # 2. check for meta tag with attribute "name" == "title", and fetch "content" attribute