Moved enable_attributes keyword to extension: legacy_attrs.

If you have existing documents that use the legacy attributes format,
then you should enable the legacy_attrs extension for those documents.
Everyone is encouraged to use the attr_list extension going forward.
Closes #643. Work adapted from 0005d7a of the md3 branch.

1 files changed, 1 insertions, 0 deletions

diff --git a/setup.py b/setup.py
index 73c7ab3..fc9ef0b 100755
--- a/setup.py
+++ b/setup.py
@@ -78,6 +78,7 @@ setup(
             'tables = markdown.extensions.tables:TableExtension',
             'toc = markdown.extensions.toc:TocExtension',
             'wikilinks = markdown.extensions.wikilinks:WikiLinkExtension',
+            'legacy_attrs = markdown.extensions.legacy_attrs:LegacyAttrExtension',
         ]
     },
     classifiers=[