Update scripts to make them more versatile:

- Support WAV
- Directories are now name original and converted
- Keep and copy mp3 and m4a files without reencoding them
- Fix mp3convert failing when there is no cover art

mp3convert

@@ -1,13 +1,13 @@
 #!/bin/bash
 
-FLAC="$1"
-OUT_DIR="mp3"
+INPUT_FILE="$1"
+OUT_DIR="$2"
 # get filename without extension
-FILENAME="${FLAC##*/}"
+BASE_NAME="${INPUT_FILE##*/}"
 # make filename with .mp3 extension
-MP3="./${OUT_DIR}/${FILENAME%.flac}.mp3"
+MP3_FILE="./${OUT_DIR}/${BASE_NAME%.*}.mp3"
 
 mkdir -p "$OUT_DIR"
 if [[ ! -f "$MP3" ]]; then
-    ffmpeg -i "$FLAC" -c:a libmp3lame -b:a 320K -map a:0 "$MP3"
+    ffmpeg -i "$INPUT_FILE" -c:a libmp3lame -b:a 320K -map a:0 -map v:0? -c:v copy "$MP3_FILE"
 fi