iqdb fixes

app/logical/iqdb/importer.rb

@@ -1,15 +1,15 @@
 module Iqdb
   class Importer
     def import!
-      IO.popen("iqdb command #{Danbooru.config.iqdb_file}", "w") do |io|
-        Post.find_each do |post|
+      Post.find_each do |post|
+        IO.popen("iqdb command #{Danbooru.config.iqdb_file}", "w") do |io|
           if File.exists?(post.preview_file_path)
             puts post.id
             hex = post.id.to_s(16)
             io.puts "add 0 #{hex}:#{post.preview_file_path}"
           end
+          io.puts "quit"
         end
-        io.puts "quit"
       end
     end
   end