OpenRPC spec sync

[aoudiamoncef]

• [ ] document all added functions
• [ ] try in sandbox /simulation/labnet
• [ ] unit tests on the added/changed features
  • [ ] make tests compile
  • [ ] make tests pass
• [ ] add logs allowing easy debugging in case the changes caused problems
• [ ] if the API has changed, update the API specification

[damip]

@aoudiamoncef can you also check if we can improve the playground ?

• make it act directly on a testnet node
• add an "intro" paragraph with a few typical usage examples
• make it easier to perform a call (check how this "method" bug can be bypassed)

[AurelienFT]

@aoudiamoncef can we merge this in prepare-testnet-16 ?

[aoudiamoncef]

@aoudiamoncef can we merge this in prepare-testnet-16 ?

I think that it's ready for main