update music scripts

private_dot_local/bin/executable_music_convert

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+
+target="$1"
+shift
+
+set -e
+
+while [[ ! -z "$1" ]]
+do
+    path="$1"
+    shift
+
+    out="$(dirname "$path")/$(basename "$path" | sed -e 's/\.[^\.]*$//').$target"
+    if [[ -z "$(echo "$out" | grep "\.$target\$")" ]]
+    then
+        out="$path.$target"
+    fi
+    ffmpeg -i "$path" "$out"
+done