Update init stack.Dockerfile

[muvaf]

• Dockerfile updated for go 1.13 and alpine 3.11
• COPY method includes all folders to cover cases where user adds another go package. Since it's multi-stage build, it should be fine to just copy everything to the build stage.

[suskin]

Awesome! 🦑

I had a nitpick, and my only other question is: what testing have we done? Otherwise, looks good to me.

I'm going to approve it in case it's already been tested, but we should test the change before merging it.

[muvaf]

@suskin I tested this by creating a new project and api via kubebuilder and then running init and build functions of the cli.

@suskin I made an addition of .dockerignore and also removed the if statements that would not add .gitignore if it doesn't exist because I thought this command might be run in a folder where git init will be run later and/or .gitignore is not added yet because it's pretty much the beginning of a project. Let me know what you think.

@suskin It's been rebased, feel free to merge the PR if you think the changes are OK.