add loader image

The following describes how to modify the image before image load.

1. Deploy a target image under your unveil-lazy-load directory in your server using FTP or FTPS.The directory may be <WordPress installed directory>/wp-content/plugins/unveil-lazy-load/
2. Modify unveil-lazy-load.php in unveil-lazy-load directory through WordPress admin menu for plugin modification.

=== Replace content of $dummy_image as below ===

* The description before modification.
$dummy_image = 'data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==';

* The description after modification.
$dummy_image = self::get_url('<your target image>');

For example, if you upload an image named before.png as your target image before image load.The modification will be as follows.

$dummy_image = self::get_url('before.png');

For those of use using 100% on image and have predefined image height and widths. Would it be possible to append a preload image instead of the image source?

$dummy_image = self::get_url('b.gif');
Could I echo an image in it’s place?

$dummy_image = echo '<img src="loader" title="loader" alt="loader" />';

Love the plugin!