msftidy fixes

Author: Brent Cook

modules/post/linux/gather/gnome_keyring_dump.rb

@@ -1,9 +1,8 @@
 ##
-# This module requires Metasploit: http//metasploit.com/download
+# This module requires Metasploit: http://metasploit.com/download
 # Current source: https://github.com/rapid7/metasploit-framework
 ##
 
-require 'msf/core'
 require 'bindata'
 
 class MetasploitModule < Msf::Post