The command 'icingacli setup config directory' actually produces the
configuration files for Icinga Web 2 instead of the command 'icingacli
setup config webserver'.
This applies a new structure for the main doc/ and modules/*/doc tree with
01-About.md
02-Installation.md
...
This allows us to link from the main doc directory into module specific
documentation entries.
Furthermore table formatting, examples, and missing settings have been added
where applicable.
This patch also takes care about proper URL anchors and file names and directories.
fixes#2950
Jennifer Mourek
Joonas Kylmälä
Michael Friedrich