Remove title attribute with datetime data

refs #7328
Make title attribute with datetime optional

refs #7328
Add title attribute with datetime to state tile

refs #7328
Adjust title datetime since/at/on

refs #7328
Add stateName to state tile in notifications
Adjust state tile title in downtimes
Update helper time formatter to receive custom title
Merge branch 'master' into bugfix/time-tooltip-7328
Update state tile title attributes
Merge branch 'master' into bugfix/time-tooltip-7328
Fix downtime time-counter
Merge branch 'bugfix/time-tooltip-7328' into bugfix/correct-duration-formatting-6778

Conflicts:
	library/Icinga/Web/View/DateTimeRenderer.php
	library/Icinga/Web/View/helpers/format.php
	modules/monitoring/application/views/scripts/list/comments.phtml
	modules/monitoring/application/views/scripts/list/downtimes.phtml
	modules/monitoring/application/views/scripts/list/notifications.phtml
	modules/monitoring/application/views/scripts/show/components/checkstatistics.phtml
	modules/monitoring/application/views/scripts/show/components/downtime.phtml
	modules/monitoring/application/views/scripts/show/components/header.phtml