These logs are available in the actions.tree logger. They'll print a helpful
list of actions and their results in a tree-like way.
For example:
```
2022-05-12 08:57:57 actions.tree: Processing Hero Actions
2022-05-12 08:57:57 actions.tree: |-> @[(x:4, y:6)][30/30]
2022-05-12 08:57:57 actions.tree: | |-> BumpAction toward (δx:-1, δy:1) by @[(x:4, y:6)][30/30] => success=False done=False alternate=WalkAction[@]
2022-05-12 08:57:57 actions.tree: | `-> WalkAction toward (δx:-1, δy:1) by @[(x:3, y:7)][30/30] => success=True done=True alternate=None
2022-05-12 08:57:57 actions.tree: Processing Entity Actions
2022-05-12 08:57:57 actions.tree: |-> Orc with 10/10 hp at (x:4, y:5)
2022-05-12 08:57:57 actions.tree: | |-> BumpAction toward (δx:-1, δy:1) by Orc with 10/10 hp at (x:4, y:5) => success=False done=False alternate=WalkAction[o]
2022-05-12 08:57:57 actions.tree: | `-> WalkAction toward (δx:-1, δy:1) by Orc with 10/10 hp at (x:3, y:6) => success=True done=True alternate=None
2022-05-12 08:57:57 actions.tree: |-> Orc with 10/10 hp at (x:5, y:5)
2022-05-12 08:57:57 actions.tree: | |-> BumpAction toward (δx:-1, δy:1) by Orc with 10/10 hp at (x:5, y:5) => success=False done=False alternate=WalkAction[o]
2022-05-12 08:57:57 actions.tree: | `-> WalkAction toward (δx:-1, δy:1) by Orc with 10/10 hp at (x:4, y:6) => success=True done=True alternate=None
```
- Sort entities by their Euclidean distance to the hero so actions from entities
near the hero are processed first
- Fewer local variables for cleaner reading
- Pass hero into the RegerateRoomsAction, which was causing a pylint error
Move all the event handling code from Engine to EventHandler. EventHandler has a
reference to Engine and can deal with entities from its methods.
Refactor Action to take an optional Entity in its initializer. Some actions
don't require an Entity, but many do/will.
