Add 2 zero padding for tracknumber by default (#594)

Author: nathom

streamrip/config.toml

@@ -161,7 +161,7 @@ add_singles_to_folder = false
 folder_format = "{albumartist} - {title} ({year}) [{container}] [{bit_depth}B-{sampling_rate}kHz]"
 # Available keys: "tracknumber", "artist", "albumartist", "composer", "title",
 # and "albumcomposer", "explicit"
-track_format = "{tracknumber}. {artist} - {title}{explicit}"
+track_format = "{tracknumber:02}. {artist} - {title}{explicit}"
 # Only allow printable ASCII characters in filenames.
 restrict_characters = false
 # Truncate the filename if it is greater than this number of characters