Provide a youtube template

Problem/Motivation

It seems Youtube videos don't use a template and instead rely on the $element[$delta] in src/Plugin/Field/FieldFormatter/AbleplayerRemoteVideoFormatter.php around line 120. This makes output customization difficult, without modifying the source code. For example if one wanted to add a special attribute to the video tag when Youtube was being used.

Steps to reproduce

1. Require the module via composer per instructions.
2. Delete its "templates" folder entirely.
3. Enabled the module per instructions.
4. Enable display for remote video per instructions.

Even with "templates" directory removed entirely, AbleplayerRemoteVideoFormatter.php will format the markup for Youtube.

Proposed resolution

Please provide a template and theme reference for a twig file instead of:

'#tag' => 'video',
'#attributes' => [...

Remaining tasks

User interface changes

API changes

Data model changes