Fix Timing

[draymond63]

Timing is currently a rigid system based of time spent on the feed page and the pageview swiping. This means that the time spent viewing the topic does NOT take into account

• topic loading
• flagging the topic
• viewing settings

Ideally the itemBase would have some way of knowing whether it is on screen or not, and that time would be tracked. Perhaps the algorithm should be switched to use a different metric...