/usr/share/doc/fusiondirectory-plugin-kolab-schema/Changelog.gz is in fusiondirectory-plugin-kolab-schema 1.0.8.2-5+deb8u1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/fusiondirectory-plugin-kolab-schema/changelog.gz