Rename game data files using all lowercase

...in case user has old DOS files. Add `rename` dependency.

Author: s1eve-mcdichae1

scriptmodules/ports/eduke32.sh

@@ -18,7 +18,7 @@ rp_module_section="opt"
 function depends_eduke32() {
     local depends=(
         flac libflac-dev libvorbis-dev libpng-dev libvpx-dev freepats
-        libsdl2-dev libsdl2-mixer-dev
+        libsdl2-dev libsdl2-mixer-dev rename
     )
 
     isPlatform "x86" && depends+=(nasm)
@@ -77,6 +77,9 @@ function install_eduke32() {
 function game_data_eduke32() {
     local dest="$romdir/ports/duke3d"
     if [[ "$md_id" == "eduke32" ]]; then
+        pushd "$dest"
+        rename 'y/A-Z/a-z/' *
+        popd
         if [[ ! -f "$dest/duke3d.grp" ]]; then
             mkUserDir "$dest"
             local temp="$(mktemp -d)"