Third Release

Includes the following changes.

• Enable caching.
• Update dependencies.
• Plugin does not correctly handle bind mounts
• Copying context has problems with symlinks and dot files

One fallout of upgrading is that logic to accommodate the two types of build tasks DockerBuildKitBuildImage and DockerBuildImage no longer need to account for DockerBuildImage as it is no longer used the class DockerBuildKitBuildImage now supports building with or without buildkit.