update dependencies
prepare for release
update dependencies
update dependencies
update CHANGES, dependencies
stop session before sending response
set platform to PHP 7.4 and update dependencies
remove support for disabling "Secure" cookie
ignore composer.lock with git diff
update code blocks
update API document
prepare for release
update documentation
make sure we have libxml >= 2.9.0
remove calls to libxml_disable_entity_loader

- we do not need it
- all platforms we support, i.e. Debian 9+, CentOS 7+ already
  have libxml >= 2.9.0 so it is disabled by default
implement support for sessions in memcache
update fkooman/secookie