epm play: add duckstation

pack.d/duckstation.sh

+#!/bin/sh
+
+TAR="$1"
+RETURNTARNAME="$2"
+
+. $(dirname $0)/common.sh
+
+VERSION="$(date -r "$TAR" "+%Y.%m.%d")"
+
+PKGNAME="$PRODUCT-$VERSION"
+
+cp $TAR $PKGNAME.AppImage || fatal
+
+return_tar $PKGNAME.AppImage

play.d/duckstation.sh

+#!/bin/sh
+
+PKGNAME=duckstation
+SUPPORTEDARCHES="x86_64"
+DESCRIPTION="DuckStation is an simulator/emulator of the Sony PlayStation(TM) from the official site"
+URL="https://github.com/stenzek/duckstation/releases"
+
+. $(dirname $0)/common.sh
+
+file="DuckStation-x64.AppImage"
+
+# TODO: preview, previous-latest
+SELECTOR="latest"
+
+PKGURL=$(epm tool eget --list https://github.com/stenzek/duckstation/releases $file | grep "/$SELECTOR/") || fatal "Can't get package URL"
+
+epm pack --install "$PKGNAME" "$PKGURL"