Rework endpoints usage doc and CLI options help

• Rework endpoints usage doc and CLI options help
  • Add missing <path> specification now available
  • add missing 'g1.' to g1.duniter.org
  • clarify g1.duniter.org is now based on a load balancer
  • Introduce f() to generate a clickable link
• Rework endpoints usage doc and CLI options help
• Usage doc: Clarify commands groups

Close #472 (closed)

changed milestone to %0.12.0

added CLI Doc/Website enhancement labels

assigned to @moul

requested review from @moul

approved this merge request

merged