Fixed some major bugs with implications, cleaning up the cache

expiration process and adding some additional tests.

Cleaned up the unit tests.  They should all run cleanly with rake
test:units now.

test/unit/upload_test.rb

@@ -11,6 +11,8 @@ class UploadTest < ActiveSupport::TestCase
   teardown do
     CurrentUser.user = nil
     CurrentUser.ip_addr = nil
+    
+    @upload.delete_temp_file if @upload
   end
   
   context "An upload" do    
@@ -165,4 +167,15 @@ class UploadTest < ActiveSupport::TestCase
     assert_equal(post.id, @upload.post_id)
     assert_equal("completed", @upload.status)    
   end
+  
+  should "delete the temporary file upon completion" do
+    @upload = Factory.create(:source_upload,
+      :rating => "s",
+      :uploader_ip_addr => "127.0.0.1",
+      :tag_string => "hoge foo"
+    )
+    
+    @upload.process!
+    assert(!File.exists?(@upload.temp_file_path))
+  end
 end