refs #6415 #4996 better protection for 0 actions if content tracking is used.

Delay first content tracking request a bit to make kinda sure a possible
previous pageview request is already executed. If there is a new visitor
and there are 2 tracking requests at nearly same time (eg trackPageView
and trackContentImpression) 2 visits will be created as both visitors
are basically at the same time. This is only a workaround and it this
problem might still occur. Also delay a link earlier in case an
interaction is happening to make sure the browser waits for the
interaction to be tracked.