add admin docs (checklist)

[BobSaidHi]

• Overview
  • Admin responsibilities
• Quick Start Guides
  • membersQuickSetup
  • orgMaintenanceGuide
  • repositoryQuickSetup
• Summaries
  • [-] Organization Homepage
  • Repositories Tab
  • Packages Tab
  • People Tab
  • Teams Tab
  • Projects Tab
  • Settings Tab
• Repositories tab
• People Tab
• Teams Tab
• Settings Tab
• OrgManagement
  • [-] orgDiscount
  • teamCleanup
  • [-] orgOwners