Issue #3271402 by RenatoG: Update the readme with the new settings in the...

   You'll be able to see your class added at  <div class="block ..."> element of

   a block.

 * By default block classes using a multiple field for classes and you can add

   one class per line.

   By default you can add 10 classes per block using add more and remove item

   in the block settings page, but if you need you can go to the settings page

   at /admin/config/content/block-class/settings and update this value if you

   need in the field "Quantity of classes per block".

 * The auto-complete settings is enabled by default and you can use this to

   auto-complete the classes inside of multiple class items.

 * By default on Block Class there is a textfield with 255 chars in the

   maxlength but there is a settings where you can modify if necessary. You can

   go to Administration » Configuration » Content authoring » Block Class or you

   your attributes. You need to use key | value format, and one per line. For

   example: data-block-type|info

 * "Advanded" On this field group that is closed by default you can set the

   array to be used in the Html::cleanCssIdentifier. This one is used to filter

   special chars in the classes. You can use one per line using key|value format

   example, to replace underline to hyphen:

   _|-

## BULK OPERATIONS

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