Update from 1.21.0 to 1.22.0.

<ChangeLog>

*) Feature: the ServerRequest and ServerResponse objects of Node.js

module are now compliant with Stream API.

*) Feature: support for specifying multiple directories in the "path"

option of Python apps.

*) Bugfix: a memory leak occurred in the router process when serving

files larger than 128K; the bug had appeared in 1.13.0.

*) Bugfix: apps could stop processing new requests under high load; the

bug had appeared in 1.19.0.

*) Bugfix: app processes could terminate unexpectedly under high load;

the bug had appeared in 1.19.0.

*) Bugfix: invalid HTTP responses were generated for some unusual status

codes.

*) Bugfix: the PHP_AUTH_USER, PHP_AUTH_PW, and PHP_AUTH_DIGEST server

variables were missing in the PHP module.

*) Bugfix: the router process could crash with multithreaded apps under

high load.

*) Bugfix: Ruby apps with multithreading configured could crash on start

under load.

*) Bugfix: mount points weren't unmounted when the "mount" namespace

isolation was used; the bug had appeared in 1.21.0.

*) Bugfix: the router process could crash while removing or

reconfiguring an app that used WebSocket.

*) Bugfix: a memory leak occurring in the router process when removing

or reconfiguring an application; the bug had appeared in 1.19.0.

</ChangeLog>