XE-1433: Can't create sub-wiki using Debian postgres package
XE-1425: dpkg errors during upgrade from 6.1 to 6.2
XE-1435: Explicit link creation leftover in postgresql debian package
XE-1434: Make sure to create the initial database with UTF8 encoding no matter what is the default postgresql configuration

(cherry picked from commit 322674eb2c5874244720b885cca9aecb0d078c2a)