Update scripts to select Metal mod vol 7, fall back to vol 6 if both are available.

.scripts/FreeDoom.sh

@@ -94,7 +94,9 @@ gameOption="$(dialog --backtitle "Select your Doom!" \
         --help-label "Exit" \
         --menu "Please select one" 0 0 0 "${doomGames[@]}" --stdout)"
 buttonCode=$?
-if [[ -e "${doomPath}/DoomMetalVol6.wad" ]]; then
+if [[ -e "${doomPath}/DoomMetalVol7.wad" ]]; then
+    gameOption+=" DoomMetalVol7.wad"
+elif [[ -e "${doomPath}/DoomMetalVol6.wad" ]]; then
     gameOption+=" DoomMetalVol6.wad"
 fi