Update from 1.11.0 to 1.12.0.

<ChangeLog>

*) Feature: compatibility with PHP 7.4.

*) Bugfix: descriptors leak on process creation; the bug had appeared in

1.11.0.

*) Bugfix: TLS connection might be closed prematurely while sending

response.

*) Bugfix: segmentation fault might have occurred if an irregular file

was requested.

</ChangeLog>