Properly deal with invalid images. This fixes ticket #611 which shows

a BMP masquerading as a .jpg causing us to be unable to rebuild
resizes and thumbnails.  Now if that happens, we discard the file, log
it and move on.

modules/gallery/views/simple_uploader.html.php

@@ -218,7 +218,7 @@
     var fp = new File_Progress(file);
     switch (error_code) {
     case SWFUpload.UPLOAD_ERROR.HTTP_ERROR:
-      fp.set_status("error", "<?= t("Upload error: ") ?>" + message);
+      fp.set_status("error", "<?= t("Upload error: bad image file") ?>");
       break;
     case SWFUpload.UPLOAD_ERROR.UPLOAD_FAILED:
       fp.set_status("error", "<?= t("Upload failed") ?>");