Merge changes made in Gnus trunk.

Merge changes made in Gnus trunk.

nnimap.el (nnimap-parse-line): Don't bug out oddly formed replies (bug #7311).
gnus-cite.el (gnus-article-fill-cited-article): Minimize the long-lines case by only filling the long lines.
gnus-start.el (gnus-ask-server-for-new-groups): Return the new groups.
gnus-group.el (gnus-group-find-new-groups): Display all the new groups.
gnus-start.el (gnus-find-new-newsgroups): Return the list of new groups.
nnimap.el (nnimap-request-group): Store the new updated info.
nnimap.el (nnimap-request-group): Select the group when we don't know whether it exists or not.