Add README.md file

Hi, I have added README.md and created MR. Please review it.

Hi nilesh.addweb

I reviewed your MR!4 and I have some concerns about the readability of the module.
you can easily copy the machine name of a field with a single click. to you can easily copy a field's machine name with a single click.
Visit content type you want to add copy field feature and edit content type page admin/structure/types/manage/article, here you can enable or disable copy field feature. to Visit the content type you want to add copy field feature and edit the content type page admin/structure/types/manage/article, here you can enable or disable copy field feature.
After enable this you can see new tab Manage Copy field on admin/structure/types/manage/article to After enabling this you can see a new tab Manage Copy field on admin/structure/types/manage/article
Copy field machine name to clipboard and past it whereever you want to Copy field machine name to clipboard and past it wherever you want

Thanks for reviewing, I have updated README.md as per #5, Please review it.

I checked the ReadMe.md file and it seems it is working as expected. Moving it to RTBC.

I have referred to this doc for Reference:- https://www.drupal.org/docs/develop/managing-a-drupalorg-theme-module-or...

ReadMe File:- https://git.drupalcode.org/issue/copy_field-3459826/-/blob/3459826-add-r...