Add .gitpod.yml for continuous prebuilds for speedy project startup! (#1328)

.gitpod.yml

@@ -0,0 +1,10 @@
+# Commands to start on workspace startup
+tasks:
+  - init: yarn install
+    command: yarn build
+# Once astro is on [vsx](https://open-vsx.org/), we should be able to specify it as an extension as well!
+# https://www.gitpod.io/docs/vscode-extensions
+# vscode:
+#   extensions:
+#     - astro-build.astro-vscode
+