Create async rust lesson and add chat app backend example

Author: uellenberg

sections/01_rust_projects/030_chat_app_backend/config.json

@@ -1,7 +1,23 @@
 {
+    "root": "/user",
     "defaultFile": "src/main.rs",
     "source": "https://github.com/Cratecode/rust/tree/master/sections/01_rust_projects/030_chat_app_backend",
     "showShareButton": true,
     "outputView": "console",
-    "outputViews": ["console", "web"]
+    "outputViews": ["console", "web"],
+    "run": {
+        "command": {
+            "value": "cargo run --manifest-path ~/project/user/Cargo.toml\n"
+        }
+    },
+    "commands": {
+        "0": {
+            "cmd": "cargo build --manifest-path ~/project/user/Cargo.toml",
+            "mode": "once"
+        },
+        "1": {
+            "cmd": "echo \"cd /home/user/project/user\" >> /home/user/.bashrc",
+            "mode": "once"
+        }
+    }
 }