Fix Packetstorm references

Author: jvazquez-r7

modules/auxiliary/scanner/http/wp_simple_backup_file_read.rb

@@ -22,7 +22,7 @@ def initialize(info = {})
       'References'     =>
         [
           ['WPVDB', '7997'],
-          ['URL', 'http://packetstormsecurity.com/files/131919/']
+          ['PACKETSTORM', '131919']
         ],
       'Author'         =>
         [

modules/auxiliary/scanner/http/wp_subscribe_comments_file_read.rb

@@ -22,7 +22,7 @@ def initialize(info = {})
       'References'     =>
         [
           ['WPVDB', '8102'],
-          ['URL', 'http://packetstormsecurity.com/files/132694/'],
+          ['PACKETSTORM', '132694'],
           ['URL', 'https://security.dxw.com/advisories/admin-only-local-file-inclusion-and-arbitrary-code-execution-in-subscribe-to-comments-2-1-2/']
         ],
       'Author'         =>

modules/exploits/unix/webapp/wp_holding_pattern_file_upload.rb

@@ -33,7 +33,7 @@ def initialize(info = {})
         [
           ['CVE', '2015-1172'],
           ['WPVDB', '7784'],
-          ['URL', 'http://packetstormsecurity.com/files/130282/WordPress-Holding-Pattern-0.6-Shell-Upload.html']
+          ['PACKETSTORM', '130282']
         ],
       'DisclosureDate'  => 'Feb 11 2015',
       'Platform'        => 'php',

modules/exploits/unix/webapp/wp_worktheflow_upload.rb

@@ -28,7 +28,7 @@ def initialize(info = {})
         [
           ['WPVDB', '7883'],
           ['EDB', '36640'],
-          ['URL', 'http://packetstormsecurity.com/files/131294/WordPress-Work-The-Flow-2.5.2-Shell-Upload.html']
+          ['PACKETSTORM', '131294']
         ],
       'Privileged'     => false,
       'Platform'       => 'php',