add new getmail formula

Signed-off-by: Adam Vandenberg <flangy@gmail.com>

* Bump to 4.20.0
* Install to libexec and link scripts into bin

Formula/getmail.rb

@@ -0,0 +1,16 @@
+require 'formula'
+
+class Getmail <Formula
+  url 'http://pyropus.ca/software/getmail/old-versions/getmail-4.20.0.tar.gz'
+  homepage 'http://pyropus.ca/software/getmail/'
+  md5 '33a090d62b6039e0a8df4c3da545d851'
+
+  def install
+    libexec.install 'getmailcore'
+    bin.mkpath
+    %w[ getmail getmail_fetch getmail_maildir getmail_mbox ].each do |f|
+      libexec.install f
+      ln_s libexec+f, bin
+    end
+  end
+end