Item12839: Revert  back to more secure REST defaults

After IRC discussion,  A more detailed warning message has been added if
any defaults have been applied.  If LegacyRESTSecurity is enabled, then
the warning message will also recommend that the handler be examined.

Update JQuery, NatEdit and Updates plugins to  set a complete security
profile.

This will all be reviewed in the release meeting.

git-svn-id: http://svn.foswiki.org/trunk/core@17727 0b4bb1d4-4e5a-0410-9cc4-b2b747904278