add sequences visualisation

[juliangruber]

When using sequences, like 10s,90s,10s,90s it would be killer to have one row of something like this:

In the top left, right next to the return to input link.

For example, with the above mentiond alert and when you're in the 3rd timer, 10s and 90s would be marked as done, the 2nd 10s would be marked as active and the last one would have a third state.