[docs] PreOS: English nitpicking

See merge request ungleich-public/cdist!820

E.g.

16.10. __block
16.11. __ccollect_source
16.12. __cdist
16.13. __cdistmarker
16.14. __check_messages

insted of

16.10. cdist-type__block(7)
16.11. cdist-type__ccollect_source(7)
16.12. cdist-type__cdist(7)
16.13. cdist-type__cdistmarker(7)
16.14. cdist-type__check_messages(7)

Resolves #796.

Fixes gitlab #790.

[PACKAGE-UPDATE-INDEX]: Bugfix of the alpine part of the __package_update_index type

See merge request !818

Redefine/reimplement CDIST_ORDER_DEPENDENCY

See merge request ungleich-public/cdist!815

Update documentation.

CDIST_ORDER_DEPENDENCY now defines type order dependency context.
cdist (emulator) maintains global state variables, as files,
order_dep_state and typeorder_dep, and per object state variable,
as file, typeorder_dep.

If order_dep_state exists then this defines that order dependency is
turned on.
If order_dep_state does not exist then order dependency is turned off.

If order dependency is on then objects created after it is turned on are
recorded into:
    * global typeorder_dep, in case of init manifest
    * object's typeorder_dep, in case of type's manifest.

If order dependency is on then requirement is injected, where object
created before current, is read from:
    * global typeorder_dep, in case of init manifest
    * object's typeorder_dep, in case of type's manifest.

Every time order dependency is turned off, typeorder_dep files are
removed, which means that type order list is cleared, context is
cleaned.

In the end cdist cleans after itself, i.e. mentioned files are removed.

When running type manifest is finished typeorder_dep file is removed.
When running config finishes global typeorder_dep and order_dep_state
files are removed.

Global type order recording is untouched.
Furthermore, for completeness, type order is now recorded for each object
too.

This reverts commit 073523be, reversing
changes made to 56435492.

This reverts commit e4421990.

__clean_path: use __directory and __file types for better clarity

See merge request ungleich-public/cdist!816

give error msg to stderr

See merge request ungleich-public/cdist!813

__hostname: silence grep exit 1, when os_version is not numeric

See merge request ungleich-public/cdist!814

on Debian Sid os_version returns 'bullseye/sid'

__apt_key: use mktemp for unique temporary gpg home

See merge request ungleich-public/cdist!812

add `--msgcache`-parameter to support passive clients (__xymon_client)

See merge request ungleich-public/cdist!811

add parameters for ownership and generic rsync-options (__xymon_config)

See merge request ungleich-public/cdist!810