fix(contrib/ci/*): fix scripts

[vdice]

Now containers are being cleaned up; Add contrib/ci/*.sh to test-style target; Fix resulting shellcheck errs

Previously, containers would remain after successful test run (trap ... INT TERM didn't account for normal exit 0):

 $ docker ps -a
CONTAINER ID        IMAGE                                COMMAND                  CREATED             STATUS                      PORTS               NAMES
655550df9bbf        quay.io/vdice/postgres:git-27b4e65   "/docker-entrypoin..."   5 minutes ago       Up 5 minutes                5432/tcp            gifted_perlman
64ab00475525        quay.io/deisci/minio:canary          "boot server /home..."   7 minutes ago       Up 7 minutes                                    naughty_visvesvaraya
f2ac81dccbe5        quay.io/vdice/postgres:git-27b4e65   "/docker-entrypoin..."   8 minutes ago       Up 8 minutes                5432/tcp            gracious_allen
b9c08a78729b        deis/swift-onlyone:git-8516d23       "/bin/sh -c /usr/l..."   10 minutes ago      Up 10 minutes               8080/tcp            onlyone
b423f21e46d7        busybox                              "sh"                     10 minutes ago      Exited (0) 10 minutes ago                       SWIFT_DATA

[deis-bot]

@paulczar, @bacongobbler and @mboersma are potential reviewers of this pull request based on my analysis of git blame information. Thanks @vdice!