Create Alpine/APK package for Deno

Using Deno inside of an Alpine docker image is currently not super easy because you need to manually install it and add it to the path. If there were an Alpine APK package for it, it could be a simple matter of adding the following to your Dockerfile:

`RUN apk add deno`

This would be incredibly valuable for my team since we use Deno scripts in lots of places where we'd normally use Bash scripts. Since build processes are often complex, require multiple commands, and need to run on different environments, scripts are an ideal way to run them. We absolutely loathe writing Bash scripts, and the sooner we can get Deno into an environment so we can stop defaulting to Bash, the happier we are.