Updated discussion defaults

Property	Value
description	Hardened the default comment and moderation settings away from stock WordPress behavior.

• Disabled link notifications from other blogs.
• Disabled link notifications on new posts.
• Disabled comments on new posts by default.
• Required comment authors to provide name and email.
• Required users to be registered and logged in before commenting.
• Left automatic comment closing disabled.
• Kept the comment cookies opt-in enabled.
• Enabled threaded comments with a depth of 8.
• Enabled comment pagination with 48 top-level comments per page, using the last page first and newer comments at the top.
• Enabled email notifications for new comments and moderation events.
• Left manual approval of every comment disabled.
• Required a previously approved comment before a commenter can post without moderation.
• Set the moderation threshold to 2 links.
• Shipped the starter with populated moderation and disallowed keyword lists.
• Left avatars enabled with rating G and default avatar Mystery Person.