Radicale is started as user radicale, so the config should be readable by this
user. Currently the config files aren't world readable, which makes the
application crash on startup.
Following rules have been applied:
- script starts with shebang !#/bin/sh followed by blank line,
- script ends with exit 0 prepended by blank line,
- only stderr of adduser, addgroup or passwd is redirected to /dev/null,
- getent passwd/group instances has been removed,
- manual checking of file and group existence has been removed,
- `|| true` instances has been removed.
Comments and line wrapping have been preserved.