add a general 'generate_csrf_token()' function

gallery_dl/util.py

@@ -16,6 +16,7 @@ import time
 import shutil
 import string
 import _string
+import hashlib
 import sqlite3
 import datetime
 import operator
@@ -60,6 +61,10 @@ def raises(cls):
     return wrap
 
 
+def generate_csrf_token():
+    return hashlib.md5(str(time.time()).encode()).hexdigest()
+
+
 def combine_dict(a, b):
     """Recursively combine the contents of 'b' into 'a'"""
     for key, value in b.items():