Refactored module layout and corrected formatting lint errors

[cppmonkey]

Utilising Ansible-Lint v4.2, various warnings have been cleared.

Tested by running, with my fork within ~/.ansible/roles/geonode.geonode-unwind
$ ansible-lint geonode.yml

---
- hosts: webservers
  remote_user: ubuntu
  vars:
    app_name: my_geonode
    github_user: GeoNode
  roles:
    - { role: geonode.geonode-unwind }

tasks, hosts and connection settings have been commented out in tasks/dbservers.yml and delete_dbservers.yml

A number of sections have been expanded to improve maintainability.
Functionality hasn't been changed