Improve structure of MongoDB User Guide

[the-redback]

• examples/monitoring contains two folder:
  • builtin-prometheus:
    • rbac: yamls to deploy prometheus server properly using roles
    • yamls to deploy prometheus server in non-rbac enabled cluster
  • CoreOS-Prometheus Operator:
    • rbac: yamls to deploy coreOS prometheus operator properly using roles
    • yamls to deploy coreOS prometheus operator in non-rbac enabled cluster
• examples/mongodb contains five folders:
  • Initialization: yamls for mongodb/initialization doc
  • Monitoring: yamls for mongodb/monitoing doc
  • Quickstart: yamls for mongodb/quickstart doc
  • Snapshot: yamls for mongodb/snapshot doc
  • Private-registry: yamls to deploy mongodb from private repo
• MongoDB user guide (docs/guides/mongodb/) contains one files and five folders.
  • Readme file: Contains overview of all docs and mongodb lifecycle
  • Quickstart:
    • Contains db Deploy, Delete, Dormant resume and wipeOut
  • Snapshot:
    • Snapshot Backup & Restore: User guide for snapshot backup & restore
    • Scheduler backup: User guide for scheduler backup
  • Monitoring: How to add monitoring properly to MongoDB
    • builtin-prometheus: User guide to monitor MongoDB using built-in Prometheus
    • CoreOS-Prometheus: User guide to monitor MongoDB using CoreOS Prometheus Operator
  • Initialization:
    • using init Script: User guide to initialize MongoDB using Init Script
    • using snapshot: User guide to initialize MongoDB using Snapshot
    • Private Registry:
    • use-private-registry: User guide to deploy mongodb from private repo
• Updated Installation guide