Revise some CLI options and adjust the docs

Some revisiting the CLI tool:

• --textx-debug: do we need this?

• rethink whether we still need --qadapter-file

• --no-unique-launchdir --no-duplicate-detection --on-demand: should trigger warnings similar to -u and -r in instant and deferred modes

• the wfengine object YAML dump by texts is not included/explained in the docs. We should either deactivate the dump or explain how to use it, e.g. by calling wfengine --load-from-file wfengine-d8d3214e1ade42aaa1f401c8dca6876c.yaml.

• add a step for testing and resetting (in case of a new empty database) the launchpad in the installation section