Proxy input should be taken during initial run of pf9-cli

[piyush271291]

When the pf9-cli is first triggered during prepping a node, it should ask for proxy information so the tasks like Downloading Platform9 installers etc. are using the proxy.

For Mavenir, we are working around this today by editing the following tasks.

i) vi pf9/pf9-venv/lib/python2.7/site-packages/pf9/express/roles/pf9-hostagent/tasks/classic-hostagent-setup.yml

- name: Download Platform9 installers
  script: files/pf9_get_hostagent.py --account_endpoint "{{du_fqdn}}" --region "{{du_region}}" --token "{{du_token}}" --proxy http://10.1.20.57:80 --platform
 "{{ansible_os_family|lower}}"
  args:
    chdir: /tmp
    executable: "{{ ansible_python.executable }}"
    register: agent_install
  when: proxy_url is undefined
- name: Download Platform9 installers
  script: files/pf9_get_hostagent.py --account_endpoint "{{du_fqdn}}" --region "{{du_region}}" --token "{{du_token}}" --proxy http://10.1.20.57:80 --platform
 "{{ansible_os_family|lower}}"
  args:
    chdir: /tmp
    executable: "{{ ansible_python.executable }}"
    register: agent_install
  when: proxy_url is defined
ii) vi pf9/pf9-venv/lib/python2.7/site-packages/pf9/express/roles/pf9-hostagent/tasks/classic-packages.yml
- name: set proxy variable
  set_fact:
    proxy: "{{'--proxy='+ proxy_url if proxy_url is defined else ''}}"
	 proxy: "{{' --proxy=http://10.1.20.57:80 ' }}"

we already have a provision for proxy information in pf9-express in express.conf located at - <working_dir>/pf9/db.