moved all timing variables to configuration profile keys

[mpanighetti]

• moved all timing variables to configuration profile keys:
  • DeferralPeriod: number of seconds between deferral prompts
  • HardRestartDelay: number of seconds between soft and hard restart attempts
  • PromptTimeout: number of seconds before script prompts time out
  • UpdateDelay: number of seconds between final alert and soft restart attempt
• regrouped all configuration profile keys in script reference and README by category
• added munkipkg run steps and prerequisites
• added link to munkipkg README for more information