Merge pull request #14 from dada513/flathub

Change flatpak to flathub

README.md

@@ -14,7 +14,7 @@ Several source build packages are available, along with experimental pre-built g
 
 - An [AUR package](https://aur.archlinux.org/packages/polymc-git/) is available.
 - A Gentoo ebuild is available in the [swirl](https://git.swurl.xyz/swirl/ebuilds) overlay, named `games-action/polymc`. Check the README for instructions on how to add the overlay.
-- A Flatpak is available. Instructions on building it can be found in [packages/flatpak/BUILDING.md](packages/flatpak/BUILDING.md).
+- A Flatpak is available in [Flathub](https://flathub.org/apps/details/org.polymc.PolyMC). You can install it from there or build it yourself using [this source](https://github.com/flathub/org.polymc.PolyMC)
 - Generic, prebuilt packages (archived by version) can be found [here](https://packages.polymc.org/) ([latest](https://packages.polymc.org/latest))
 - Last build status: https://jenkins.polymc.org/job/PolyMC/lastBuild/
 - [Linux (AMD64) System](https://packages.polymc.org/latest/lin64-system/lin64-system.tar.zst) ([SHA256](https://packages.polymc.org/latest/lin64-system/lin64-system.tar.zst.sha256)) - this is a generic system package intended to be used as a base for making distro-specific packages.