Prepare for 0.9.19 release

Merge branch 'next'

Note 0.9.17 release date

Note 0.9.16 release date

Fix setuid bit on /usr/bin/sudo, bump version to 0.9.15.

Closes phusionGH-148.

Bump version to 0.9.14

Note 0.9.13 release date

Update changelog

Note release date

Fix syslog-ng.

The system() source in the default syslog-ng config file does
not work in Docker because it tries to access /proc/kmsg,
which is not allowed due to Docker's privileges. We replace
it by a source that only reads from /dev/log.