Add support for codespaces

.devcontainer/Dockerfile

@@ -0,0 +1,15 @@
+FROM mcr.microsoft.com/vscode/devcontainers/base:debian-10
+
+ENV DENO_INSTALL=/deno
+RUN mkdir -p /deno \
+    && curl -fsSL https://deno.land/x/install/install.sh | sh \
+    && chown -R vscode /deno
+
+ENV PATH=${DENO_INSTALL}/bin:${PATH} \
+    DENO_DIR=${DENO_INSTALL}/.cache/deno
+
+RUN deno cache deps.ts
+
+# [Optional] Uncomment this section to install additional OS packages.
+# RUN apt-get update && export DEBIAN_FRONTEND=noninteractive \
+#    && apt-get -y install --no-install-recommends <your-package-list-here>

.devcontainer/devcontainer.json

@@ -0,0 +1,23 @@
+{
+    "name": "Deno",
+    "dockerFile": "Dockerfile",
+
+    // Set *default* container specific settings.json values on container create.
+    "settings": { 
+        "terminal.integrated.shell.linux": "/bin/bash"
+    },
+
+    // Add the IDs of extensions you want installed when the container is created.
+    "extensions": [
+        "denoland.vscode-deno"
+    ],
+
+    // Use 'forwardPorts' to make a list of ports inside the container available locally.
+    // "forwardPorts": [],
+
+    // Uncomment to use the Docker CLI from inside the container. See https://aka.ms/vscode-remote/samples/docker-from-docker.
+    // "mounts": [ "source=/var/run/docker.sock,target=/var/run/docker.sock,type=bind" ],
+
+    // Uncomment to connect as a non-root user. See https://aka.ms/vscode-remote/containers/non-root.
+    // "remoteUser": "vscode"
+}