Symptoms:
```
extras/dialer/time-scope-probe-cgroup:31:18: arithmetic expressions must consist of names and numbers
extras/dialer/time-scope-probe-cgroup: run shfmt -i 4 -w extras/dialer/time-scope-probe-cgroup
extras/dialer/time-scope-probe-proc:28:18: arithmetic expressions must consist of names and numbers
extras/dialer/time-scope-probe-proc: run shfmt -i 4 -w extras/dialer/time-scope-probe-proc
extras/in_parallel.sh:29:16: arithmetic expressions must consist of names and numbers
extras/in_parallel.sh: run shfmt -i 4 -w extras/in_parallel.sh
```
Visible on https://circleci.com/gh/kinvolk/scope/980
* circle.yml: deploy master with non-upstream hub accounts
Since b4abe582f4, images are tagged on
Docker Hub. But this was not working for non-upstream Docker Hub
accounts. This patch should fix that.
Symptoms: https://circleci.com/gh/kinvolk/scope/23
> The push refers to a repository [docker.io/kinvolk/scope] (len: 1)
> error getting tags for kinvolk/scope: Tag does not exist for
> master-b89e9ec
Also, ensure that the Docker tag name does not include any '/'.
Symptoms: https://circleci.com/gh/kinvolk/scope/24
> docker tag weaveworks/scope weaveworks/scope:alban/hub1-ef739d9
> repository name component must match "[a-z0-9]+(?:[._-][a-z0-9]+)*"
* extras/in_parallel.sh: ensure unique schedule name
Use CircleCI environment variables as documented on:
https://circleci.com/docs/environment-variables/
Symptoms:
> $ cd $SRCDIR/extras; ./build_on_circle.sh
> Doing graphviz/graphviz
> make: *** No rule to make target `graphviz/graphviz'. Stop.
See: https://github.com/weaveworks/scope/pull/1655#issuecomment-232696357
* circle.yml: separate wcloud deployment
Do not run wcloud for non-weaveworks builds, as suggested by
https://github.com/weaveworks/scope/pull/1655#discussion_r71179373
