Because the detection of the webroot is not that good, it was removed.
Now, the object id contains the full path of the nextcloud installation.
This changes the installation process a bit, as it will download the
tarball to /tmp rather the webroot.
Also, this commit contains a bit overhaul work.
The type now handles the case when the data directory will be moved to
an other location. To this, adjustment to the "maintainer mode" on
setting and the manpage.
Some database parameters are required if the type is `mysql` or `pgsql`.
Also, the variants of the parameter --database-type decreased to those
that work with the configuration, as it is directly mapped to the
parameter.
The functions in `map-conf-changes.sh` where extended to support the
conditional mandatory argument to throw an error if this parameter is
set.
