Merge dashpay#6055: refactor: use new type of composite commands for quorum NNN

b478406 refactor: clean-up, missing const in rpc/quorums (Konstantin Akimov)
50c99e8 fix: adopt platform restriction for new composite commands (Konstantin Akimov)
e3c4d66 refactor: quorum sign methods (Konstantin Akimov)
2af9d86 refactor: use new approach for rpc quorums NNN (Konstantin Akimov)

Pull request description:

  ## Issue being fixed or feature implemented
  See dashpay#6051

  ## What was done?
  Commands starting from 'quorum ...' uses new a new way to make composite commands.

  ## How Has This Been Tested?
  Run unit/functional tests.
  Please notice, there's required extra changes for platform restrictions, the subcommand is no more first argument, but part of command, space separated.

  ## Breaking Changes
  N/A

  ## Checklist:
  - [x] I have performed a self-review of my own code
  - [x] I have commented my code, particularly in hard-to-understand areas
  - [x] I have added or updated relevant unit/integration/functional/e2e tests
  - [x] I have made corresponding changes to the documentation
  - [x] I have assigned this pull request to a milestone

ACKs for top commit:
  UdjinM6:
    utACK b478406
  PastaPastaPasta:
    utACK b478406

Tree-SHA512: c53856a3f45fee44a8130876ed4545f6f2c0f59f74e4d4745e7354097fee3a74ed526cc8160de532dbb4aeb81b82638ee912a0961b910692e78889baa2c976c3

Author: PastaPastaPasta