Tools: Add a script for showing the metadata of a file

This seems generally useful for determining what we should save or try
to display in the track database.

Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>

tools/show_tags.py

@@ -0,0 +1,24 @@
+#!/usr/bin/python
+# Copyright 2020 (c) Anna Schumaker
+#
+# Use Mutagen to show the metadata of the requested file
+import mutagen
+import os
+import sys
+
+if len(sys.argv) != 2 or not os.path.isfile(sys.argv[1]):
+    print(f"Usage: {sys.argv[0]} FILE")
+    sys.exit(1)
+
+print()
+print(f"Reading file {sys.argv[1]}:")
+
+tags = mutagen.File(sys.argv[1])
+keys = tags.keys()
+keys.sort()
+if "metadata_block_picture" in keys:
+    tags["metadata_block_picture"] = True
+
+for key in keys:
+    print(f"    {key}: {tags[key]}")
+print()