[PATCH] Make it possible to see the attack rate of units and buildings (number of attacks per second)

[sanderd17]

It's nice if you can see the attack rate of an entity. It doesn't help if you see the attack strength is 2 times bigger, but you don't see the attacks happen 4 times less often f.e.

For buildings, it could help with determining how many arrows certain units add to the building.

The problem with this patch is that the enemy can also calculate how many units you have in the building. But he could also estimate that by letting the building fire once (and get an idea of the number of arrows released). And IMO, this "showing too much info to the enemy" was already the case in the building panel.

[sanderd17]

In 14555:

Show the number of attacks per second to show users some attack speed, without showing the actual timers, or calcualtion of the number of arrows. Fixes #2352