Move all crates into a crates directory (#1940)

.github/workflows/rust.yml

@@ -209,4 +209,4 @@ jobs:
           override: true
 
       - run: cargo check --features wgpu --target aarch64-linux-android
-        working-directory: eframe
+        working-directory: crates/eframe

Cargo.toml

@@ -1,16 +1,16 @@
 [workspace]
 resolver = "2"
 members = [
-    "egui_demo_app",
+    "crates/egui_demo_app",
-    "egui_demo_lib",
+    "crates/egui_demo_lib",
-    "egui_extras",
+    "crates/egui_extras",
-    "egui_glium",
+    "crates/egui_glium",
-    "egui_glow",
+    "crates/egui_glow",
-    "egui-wgpu",
+    "crates/egui-wgpu",
-    "egui-winit",
+    "crates/egui-winit",
-    "egui",
+    "crates/egui",
-    "emath",
+    "crates/emath",
-    "epaint",
+    "crates/epaint",
 
     "examples/*",
 ]