[doc] Explain that the opposite of --no-overwrites is --no-continue.

README.md

@@ -255,12 +255,15 @@ Alternatively, refer to the [developer instructions](#developer-instructions) fo
     --restrict-filenames                 Restrict filenames to only ASCII
                                          characters, and avoid "&" and spaces in
                                          filenames
-    -w, --no-overwrites                  Do not overwrite files
+    -w, --no-overwrites                  Do not overwrite files. (For the
+                                         opposite, see --no-continue.)
     -c, --continue                       Force resume of partially downloaded
                                          files. By default, youtube-dl will
                                          resume downloads if possible.
     --no-continue                        Do not resume partially downloaded
-                                         files (restart from beginning)
+                                         files: Instead, restart from the
+                                         beginning and ruthlessly overwrite
+                                         existing files.
     --no-part                            Do not use .part files - write directly
                                          into output file
     --no-mtime                           Do not use the Last-modified header to

youtube_dl/options.py

@@ -724,15 +724,15 @@ def _comma_separated_values_options_callback(option, opt_str, value, parser):
     filesystem.add_option(
         '-w', '--no-overwrites',
         action='store_true', dest='nooverwrites', default=False,
-        help='Do not overwrite files')
+        help='Do not overwrite files. (For the opposite, see --no-continue.)')
     filesystem.add_option(
         '-c', '--continue',
         action='store_true', dest='continue_dl', default=True,
         help='Force resume of partially downloaded files. By default, youtube-dl will resume downloads if possible.')
     filesystem.add_option(
         '--no-continue',
         action='store_false', dest='continue_dl',
-        help='Do not resume partially downloaded files (restart from beginning)')
+        help='Do not resume partially downloaded files: Instead, restart from the beginning and ruthlessly overwrite existing files.')
     filesystem.add_option(
         '--no-part',
         action='store_true', dest='nopart', default=False,