* docs: split changelog into separate file
See #137
* docs: add information to Plugin header
Fix#138
* docs: update WP readme
* docs: remove FAQs
* docs: remove installation instructions
These were causing the FAQ section to render incorrectly
when viewed in the [preview validator][validator].
Also, the [WP Plugin Handbook][wp-handbook] says that:
> If your plugin has no custom install settings, it's
> okay to omit this section.
[validator]: https://wpreadme.com/
[wp-handbook]: https://developer.wordpress.org/plugins/wordpress-org/how-your-readme-txt-works/#installation
* docs: update links, versions, add extra changelog items
* docs: lower version to stable ver
