Add devcontainer.json

devcontainer.json allows github's codespaces to be created with bumble's dependencies already installed

.devcontainer/devcontainer.json

@@ -0,0 +1,30 @@
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the
+// README at: https://github.com/devcontainers/templates/tree/main/src/python
+{
+	// Or use a Dockerfile or Docker Compose file. More info: https://containers.dev/guide/dockerfile
+    "image": "mcr.microsoft.com/devcontainers/universal:2",
+
+	// Features to add to the dev container. More info: https://containers.dev/features.
+	// "features": {},
+
+	// Use 'forwardPorts' to make a list of ports inside the container available locally.
+	// "forwardPorts": [],
+
+	// Use 'postCreateCommand' to run commands after the container is created.
+    "postCreateCommand": 
+        "python -m pip install '.[build,test,development,documentation]'",
+
+    // Configure tool-specific properties.
+    "customizations": {
+        // Configure properties specific to VS Code.
+        "vscode": {
+            // Add the IDs of extensions you want installed when the container is created.
+            "extensions": [
+                "ms-python.python"
+            ]
+        }
+    }
+
+	// Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.
+	// "remoteUser": "root"
+}