add epm play steam (but hidden from play list)

prescription.d/steam.sh

+#!/bin/sh
+
+# TODO: common place
+fatal()
+{
+    echo "FATAL: $*" >&2
+    exit 1
+}
+
+PKGNAME=steam-launcher
+
+if [ "$1" = "--remove" ] ; then
+    epm remove $PKGNAME
+    exit
+fi
+
+[ "$1" != "--run" ] && exit #echo "Install Steam for Linux from the official site" && exit
+
+[ "$($DISTRVENDOR -a)" != "x86_64" ] && echo "Only x86_64 is supported" && exit 1
+
+epm install "https://cdn.akamai.steamstatic.com/client/installer/steam.deb"

repack.d/steam-launcher.sh

+#!/bin/sh -x
+
+# It will be run with two args: buildroot spec
+BUILDROOT="$1"
+SPEC="$2"
+
+PRODUCT=steam-launcher
+
+subst "s|.*/etc/apt.*||" $SPEC
+