fix-header.py: Preserve shebang

Preserve shebang at start of file. Also ran fix-header.py on itself.

scripts/tools/fix-header.py

@@ -4,6 +4,7 @@
 # Picard, the next-generation MusicBrainz tagger
 #
 # Copyright (C) 2020 Laurent Monin
+# Copyright (C) 2020 Philipp Wolfer
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU General Public License
@@ -19,6 +20,7 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 
+
 import argparse
 from collections import defaultdict
 import glob
@@ -114,6 +116,9 @@ def parse_file(path):
     with open(path) as f:
         lines = f.readlines()
         found = defaultdict(lambda: None)
+        if lines[0].startswith('#!'):
+            found["shebang"] = lines[0].rstrip()
+            del lines[0]
         for num, line in enumerate(lines):
             if line.startswith("# Automatically generated"):
                 found['autogenerated'] = num
@@ -232,6 +237,7 @@ def fix_header(path):
     has_content = bool(before + after)
 
     parts = list(filter(None, [
+        found["shebang"],
         CODING_TEXT.strip(),
         LICENSE_TOP.strip(),
         new_copyright.strip(),