This is the second part to D681.
- Allow garrisoning in allied buildings
- Replace the alert level with matching classes
- Add a bell at the market for trade carts
- Change the GUI to always display two buttons: alert (garrison) and safe (back to work)
I've also added a timer so that the raise or end alert is only done once per turn. (We search for units and garrison holders, so I'm assuming there's some kind of performance hit.)
Here's the GUI change to the market. The icons are slightly smaller so they don't overlap with the portrait. Now four digit prices slightly run over the icons, but there's not room to make the icons bigger and the font looks bad at a smaller size. Because we can't really fix this, I'm saying it's not a big deal.
(I decided to leave hotkeys for another day.)