Bump dependencies (#10)

The biggest version bump is Amethyst from 0.12 to 0.13. This has a
breaking change in the example, where world.read_resource now returns
a Fetch<ScreenDimensions> instead of a &ScreenDimensions.

Cargo.toml

@@ -5,8 +5,8 @@ authors = ["Hilmar Wiegand <me@hwgnd.de>"]
 edition = "2018"
 
 [dependencies]
-amethyst = "0.12.0"
-log = { version = "0.4.6", features = ["serde"] }
+amethyst = "0.13.0"
+log = { version = "0.4.8", features = ["serde"] }
 
 [features]
 default = ["vulkan"]

src/state.rs

@@ -21,7 +21,7 @@ impl SimpleState for MyState {
         // Get the screen dimensions so we can initialize the camera and
         // place our sprites correctly later. We'll clone this since we'll
         // pass the world mutably to the following functions.
-        let dimensions = world.read_resource::<ScreenDimensions>().clone();
+        let dimensions = (*world.read_resource::<ScreenDimensions>()).clone();
 
         // Place the camera
         init_camera(world, &dimensions);