feat: docker context support

[developer-guy]

There is a concept in Docker called contexts. With the use of contexts, we can work with different Docker Hosts simultaneously on the host by switching between them.

For example:

$ docker context list
NAME                TYPE                DESCRIPTION                               DOCKER ENDPOINT                                         KUBERNETES ENDPOINT   ORCHESTRATOR
default *           moby                Current DOCKER_HOST based configuration   unix:///var/run/docker.sock                                                   swarm
desktop-linux       moby                                                          unix:///Users/xxxx.xxx/.docker/run/docker.sock
vm01     moby                some description                          tcp://xxxxx:2376
vm02 moby                some description                          tcp://xxxx:2376

We can easily switch between them by using the use command.

$ docker context use vm01
vm01

It would be better to see the information on the Terminal to understand which Docker Context are we currently working on.