Dockerfile with release builds

[shaneutt]

For early builds we just used archlinux and a debug build of the dataplane components in dataplane/Dockerfile as this was fine for early testing. The purpose of this task is to harden this:

• [ ] switch to a different base, perhaps alpine with a musl libc build
• [ ] enable release builds for images by default
• [ ] (optionally) add debug builds as a special tag