add remove_file() and remove_directory() helpers

these functions call os.unlink() or os.rmdir()
while catching and suppressing potential OSErrors

gallery_dl/postprocessor/zip.py

@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 
-# Copyright 2018-2019 Mike Fährmann
+# Copyright 2018-2020 Mike Fährmann
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 2 as
@@ -9,17 +9,17 @@
 """Store files in ZIP archives"""
 
 from .common import PostProcessor
+from .. import util
 import zipfile
-import os
 
 
 class ZipPP(PostProcessor):
 
     COMPRESSION_ALGORITHMS = {
         "store": zipfile.ZIP_STORED,
-        "zip": zipfile.ZIP_DEFLATED,
+        "zip"  : zipfile.ZIP_DEFLATED,
         "bzip2": zipfile.ZIP_BZIP2,
-        "lzma": zipfile.ZIP_LZMA,
+        "lzma" : zipfile.ZIP_LZMA,
     }
 
     def __init__(self, pathfmt, options):
@@ -64,18 +64,11 @@ class ZipPP(PostProcessor):
             self.zfile.close()
 
         if self.delete:
-            try:
-                # remove target directory
-                os.rmdir(self.path)
-            except OSError:
-                pass
+            util.remove_directory(self.path)
 
             if self.zfile and not self.zfile.NameToInfo:
-                try:
-                    # delete empty zip archive
-                    os.unlink(self.zfile.filename)
-                except OSError:
-                    pass
+                # remove empty zip archive
+                util.remove_file(self.zfile.filename)
 
 
 __postprocessor__ = ZipPP