Use docker-slim for smaller images

[oxr463]

🚀 Feature Request

Idea:

This tool can be used to decrease image sizes:

• https://github.com/docker-slim/docker-slim

Problems that want to be solved:

Currently, image sizes are rather large.

[trinhpham]

Could you please help make a sample to see how much we can save, @oxr463 ? IMO, it won't save much since our image size is big because of the base image of the emulator, but any optimizations should be welcomed