Add feature to choose which services to start with docker-compose up

[chipkillmar]

Sometimes we prefer to run docker-compose up -d service1 service2 ... where this represents a proper subset of services. It helps reduce startup time, and allows for better reuse of Docker Compose files.

These changes add to the DockerComposeRule builder to specify which services to start, e.g.

.addServicesToStart("db") // Only start the db container.

See also: #182

[palantirtech]

Thanks for your interest in palantir/docker-compose-rule, @chipkillmar! Before we can accept your pull request, you need to sign our contributor license agreement - just visit https://cla.palantir.com/ and follow the instructions. Once you sign, I'll automatically update this pull request.

[chipkillmar]

@j-baker could you please review this pull request? Thanks in advance.

[kucera-jan-cz]

I really hope that this change will get soon into new release. Having ability to define which services should be started would help our project a lot!