Build-Time Improvement: Don't Overwrite Build Image Cache

[dOrgJelli]

Currently by default, the CLI assigns a single name to the docker build-image it constructs.

This causes a loss of caching when building 2 separate projects back to back, this is because the name is being re-used for two different project directories. The cache gets flushed because the source files are different in the project directory.

In order to fix this, we should prescribe a name to the build image. This image name can be found by:

• Looking at the build manifest's docker.name property
• Allowing the user to assign it via a command line argument
• Auto generating a random name

The build image's name can be cached in the CLI's .w3/ archive folder.

[Niraj-Kamdar]

This would be really nice improvement for devs! I also noticed some issues due to it having same name in docker networks, apparently I need to prune docker network sometimes since it creates to network with the same name.