Added a snapcraft.yaml file that dictates how to build each version. Right now, the version number must be specified in the pull branch and the zip download for the build files. I've tried several ways to put this in an env var that can be easier to update, but haven't been successful - any help with this would be appreciated.
Snap Store account link & publish are not part of this PR.
Updated the README and restructured it to include install & update information for both Snap & Flatpak. This will need to be updated once we have set up FlatHub and Snap Store releases.
I've added snap package support.