Alpine does not support python3 yet, but depot_tools enabled python3
by default recently.
Disable python3 for now.
Fixes#763.
Change-Id: I57cd414702e89cafbe1b8beee810f89760129d10
This is achieved with these techniques:
- Use Alpine as the base image, which is only ~5MB.
- Use docker's multi-stage build to keep only the result binaries in
the final image.
The new image is ~15MB after this change.
Also updated Dockerfile to use the current checkout code instead of always
sync from the latest.
Also added a .dockerignore file to ignore temporary build artifacts.
Closes#535.
Change-Id: I3c90805ebba40295e69241214ed6d7adbde465b8
KongQun Yang
Gabe Kopley
Leandro Moreira