backporting bugfixes to the v5-10 branch

[Andreas Seltenreich <andreas+ding@gate450.dyndns.org>]

I just reviewed the v5-10 branch with respect to my recent bugfixes in
the trunk, and the following would be applicable to the stable branch,
too:
	* nnweb.el (nnweb-google-parse-1): Update regexp for author and date.
	(nnweb-google-search): Respect nnweb-max-hits as upper bound.

	* gnus-srvr.el (gnus-browse-unsubscribe-group): Don't subscribe
	unsubscribed groups as if they were killed ones.  It causes duplicate
	entries in gnus-newsrc-alist.

	* mm-url.el (mm-url-insert-file-contents): Don't set Connection: Close.

Any objections to backporting them?

I'm not sure what to do with the change to gnus-find-method-for-group:

	* gnus.el (gnus-find-method-for-group): On killed/unknown groups, try
	looking up the method using GROUP's prefix before inventing a new one.
	It is used on killed/unknown groups in various places where returning
	an all-new method isn't expected by the caller.

While I can reproduce all of the bugs listed in
<news:87fyhttsum.fsf@gate450.dyndns.org> on a stable Gnus, the fix
depends on the macro gnus-group-server, which doesn't exists on the
v5-10 branch.  Maybe just inling its code is more appropriate than
adding the macro to v5-10?  I'm afraid the alternative to changing
gnus-find-method-for-group would be to locate all places where it
could be called on killed groups, and possibly fixing those.

regards,
andreas