add '-K' as shortcut for '--list-keywords'

docs/configuration.rst

@@ -156,8 +156,8 @@ general pattern specifically for ``PixivUserExtractor`` instances.
 
 The ``category`` and ``subcategory`` of all extractors are included in the
 output of ``gallery-dl --list-extractors``. For a specific URL these values
-can also be determined by using the ``--list-keywords`` command-line option
-(see the example below).
+can also be determined by using the ``-K``/``--list-keywords`` command-line
+option (see the example below).
 
 extractor.*.filename
 --------------------
@@ -169,12 +169,12 @@ Description A `format string`_ to build the resulting filename
 
             The available replacement keys depend on the extractor used. A list
             of keys for a specific one can be acquired by calling *gallery-dl*
-            with the ``--list-keywords`` command-line option.
+            with the ``-K``/``--list-keywords`` command-line option.
             For example:
 
             .. code::
 
-                $ gallery-dl --list-keywords http://seiga.nicovideo.jp/seiga/im5977527
+                $ gallery-dl -K http://seiga.nicovideo.jp/seiga/im5977527
                 Keywords for directory names:
                 -----------------------------
                 category

gallery_dl/option.py

@@ -119,6 +119,10 @@ def build_parser():
         "-j", "--dump-json", dest="list_data", action="store_true",
         help="Print JSON information",
     )
+    output.add_argument(
+        "-K", "--list-keywords", dest="list_keywords", action="store_true",
+        help="Print a list of available keywords for the given URLs",
+    )
     output.add_argument(
         "--list-modules", dest="list_modules", action="store_true",
         help="Print a list of available extractor modules",
@@ -128,10 +132,6 @@ def build_parser():
         help=("Print a list of extractor classes "
               "with description, (sub)category and example URL"),
     )
-    output.add_argument(
-        "--list-keywords", dest="list_keywords", action="store_true",
-        help="Print a list of available keywords for the given URLs",
-    )
 
     downloader = parser.add_argument_group("Downloader Options")
     downloader.add_argument(

test/test_extractors.py

@@ -67,6 +67,7 @@ skip = [
     "archivedmoe", "archiveofsins", "thebarchive",
     # temporary issues
     "imgtrex",  # 504
+    "mangazuki",  # 403
 ]
 # enable selective testing for direct calls
 if __name__ == '__main__' and len(sys.argv) > 1: