Merge chagnes made in Gnus trunk.

Merge chagnes made in Gnus trunk.

auth.texi (GnuPG and EasyPG Assistant Configuration): Mention the default now is to have two files in `auth-sources'.
nnimap.el (nnimap-open-connection-1): Delete duplicate server names when getting credentials.
gnus-util.el (gnus-delete-duplicates): New function.
nnimap.el (nnimap-credentials): Instead of picking the first port as a creation default, pass the whole port list down.  It will be completed.
auth-source.el (auth-source-search): Updated docs to talk about multiple creation choices.
 (auth-source-netrc-create): Accept a list as a value (from the search parameters) and do completion on that list.  Keep a separate netrc line with the password obscured for showing the user.
nnimap.el (nnimap-open-connection-1): Make the `nnimap-address' the first choice to `auth-source-search' so it will be used for entry creation instead of the server's Gnus-specific name.
 (nnimap-credentials): Rely on the auth-source library to select which port is actually wanted in the new netrc entry, so don't override `auth-source-creation-defaults'.