Implement templates for emails

[oxr463]

Currently defined in the source as,

#define USER_PROMPT "An email with a one-time passcode was sent to your email." \
	            "\nEnter the code at https://aka.ms/devicelogin, then press enter.\n"

Template should be stored in /etc/aad/template.d/, (See: CyberNinjas/libnss_aad#5); or similar; add this to the config file via template_dir.

Example

Contents of /etc/pam_aad.conf:

{ 
  "client": {
    "id": "{{client_id}}"
  },
  "domain": "{{domain}}",
  "group": {
    "id": "{{group_id}}"
  },
  "smtp_server": "{{smtp_server}}",
  "tenant": {
    "name": "{{organization}}.onmicrosoft.com",
    "address": "{{organization_email_address}}"
  },
  "template_dir": "{{template_dir}}"
}

Source: CyberNinjas/pam_aad#37