Adding instructions for installation on Fedora Silverblue and other rpm-ostree Fedora variants. (#161)

* Update README.md

Adding instructions for Fedora Silverblue and other rpm-ostree variants.

* Update README.md

* Update README.md

* Initial Mpris widget code

* Fixed carousel not updating widgets when CC is hidden

* Scroll to newest player when new player appears

* Updated widget style

* Clamp image radius

* Use generic type when getting config value

* Use Application icon as fallback

* Use Appname as fallback

* Show first artist in subtitle

* Button opacity is now applied only to the image child

* Treat Stopped state as paused

* Fixed linting issues

* Updated README

* Updated config and config schema

* Simplified player check

* Updated Man page

* Enable scrolling

* Updated css to include title and subtitle

* Initial widget code with Title and DND widgets

* Fixed linting issues

* Added label widget

* Added label to widgets JSON Schema

* Added default widgets

* Added info to swaync 5 man page

* Updated README with widget info

* Added ability for multiple configs per widget

* Reworked how the widget CSS classes are applied

* Fixed linting issues

* Added CSS class names to man page

Repo: https://copr.fedorainfracloud.org/coprs/erikreider/SwayNotificationCenter/

Co-authored-by: Aleksei Fedotov <aleksei@fedotov.email>

* add notifications number in text field

* include a mention about this in the README

* fix the linting issue... hopefully

* print the count as a uint directly

* Add missing build dependency and installed files in rpmbuild spec file

* Remove unrequired fish shell build dependency