Doc: fix version information.
Docs: fix icinga-web-scratch.

Wrong anchors / tags
Docs: insert "newbie" document.

Ref: #3263 enhance beginners guide
Merge branch 'master' of git.icinga.org:icinga-doc into next

Conflicts:
	de/icinga-web-scratch.xml
	en/icinga-web-scratch.xml
Docs: Typos.
Docs: drop references to Icinga 1.7 and below.

Ref: #5868
Merge branch 'master' into next

Conflicts:
	de/configmain.xml
	en/extcommands2.xml
Docs: dead link in notifications.html

Refs: #6848

Signed-off-by: Michael Friedrich <michael.friedrich@netways.de>
Docs: Error in threshold definitions.

Refs: #6877

Signed-off-by: Michael Friedrich <michael.friedrich@netways.de>
Docs #7513: add sort_status_data_by_default to config.cgi.

Refs: #5965

Signed-off-by: Michael Friedrich <michael.friedrich@netways.de>
Docs #7548: add set_sticky_acknowledgment to cgi config.

Refs: #6237

Signed-off-by: Michael Friedrich <michael.friedrich@netways.de>
Docs #6475: Apache 2.4 requires 'a2enmod cgi'.

Signed-off-by: Michael Friedrich <michael.friedrich@netways.de>
Docs #6866: update documentation for systemd usage.

Refs: #6710

Signed-off-by: Michael Friedrich <michael.friedrich@netways.de>
Docs: update versions.

Signed-off-by: Michael Friedrich <michael.friedrich@netways.de>
Remove duplicate description of exclude all custom vars