Do git submodule preparation in git

Ansible's performance was disappointing, so let's try to see if I can do
it better in pure shell. `jq` provides access to the repository
structure as exported from Zuul's variable via an intermediate JSON
file.

Change-Id: If420fe6f39eb29f8791551b7240938bbdc5d66b3
1 file changed
tree: ab21dcdc31ddaa32a2c4a92d880a9a61a15cf468
  1. README.md
  2. playbooks/
  3. zuul.yaml
README.md

Zuul jobs specific to CESNET