Markdown filter : Allow adding certain tags that needs no localization

Created by: deeagraw

In some cases, we need to flag certain sections of content within an article to be English only. In AEM, A3 Components have a "Do Not Localize" option. For sections of text that should not be localized, use the [!DONOTLOCALIZE] extension and use block quotes ( > ) to mark the entire English-only section.

Example:

>[!DONOTLOCALIZE]
>## Exporting widgets
> This section will not be localized.
> 1. Do the first step.  
>    > [!NOTE]
>    > Remember to do the first step properly.
> 1. Do the second step.

The non-translatable tag could be user-specific and hence should be configurable.