set docker service names

[mlin]

docker auto-generates service names from word lists with about 25,500 possible combinations: https://github.com/moby/moby/blob/master/pkg/namesgenerator/names-generator.go

Consequently, error-inducing collisions are expected in any set of merely a few hundred services (d=25500, p=0.5).

This has happened to me at least twice during service creation, e.g.

2019-11-24 22:33:38,950 wdl.w:TestBulkRnaPR.w:call-target.t:call-rsem_quant-1 ERROR task rsem_quant (bulk_rna_pipeline.wdl Ln 287 Col 5) failed :: error: "APIError", message: "500 Server Error: Internal Server Error (\"rpc error: code = Unknown desc = name conflicts with an existing object\")"

We need to override the service names to something with more uniqueness/entropy.

(Container names are generated with a retry loop to avoid this problem, but service names are not. https://github.com/moby/moby/blob/e511b3be894465d81c21cab35b4f292d9250a4ca/daemon/names.go#L84 https://github.com/moby/moby/blob/8840071c26093d0589edb659b329e82892e496c2/daemon/cluster/convert/service.go#L143)