add capability to restrict recipients of dokuwiki 'msg' alerts.  This is useful where message is added to the queue before authentication is initialized

This adds $INPUT in all places where it was still missing and available.
$INPUT is now also used in places where using $_REQUEST/... was okay in
order to make the code consistent.

This reverts parts of the changes from #154: Before merging the pull
request, a depth of 1 returned just the pages in the root namespace.
With the changes in the pull request, a depth of 1 also returned pages
in subnamespaces of the root namespace (as it was also tested in the test case).
This reverts this part of the changes and a depth of 1 returns just the
pages in the root namespace again.

In the case of a failed authentication initialization, the
authentication setup was simply continued with an unset $auth object.
This restores the previous behavior (before merging #141) of simply
returning after unsetting $auth. Furthermore this re-introduces the
check if $auth is set before checking $auth and removes a useless
check if $auth is true (could never be false).

changed nonexistant actionOk to actionOK

IE9 send different HTTP_ACCEPT_LANGUAGE header on ajax request. This causes different results from auth_browseruid. This patch removes the HTTP_ACCEPT_LANGUAGE from the browser id calculation.

remove security token from tpl_actiondropdown - its not necessary, we're not posting any system change

The line prefix was not actually indicating what it should indicate.
In particular, anything in a "changed" block would show a "!" even
if the entire line was added or deleted. Better to print nothing than
something that's wrong.

fix a couple of diff issues: shouldn't be any need to html encode before finding diffs; move quantifier outside regex condition

Previously the media manager created an empty namespace whenever you
opened a non-existing namespace with upload permissions. Now the current
namespace is only displayed in the tree but not actually created.

It seems, some servers require a special Status: header for sending the
HTTP status code from PHP (F)CGI to the server. This patch introduces a
new function (adopted from CodeIgniter) for simplifying the status
handling.