* master:
  Network bridge refactoring impl (#1537)
  Augment Implementer's Guide XCMP docs (#1569)
  Support `build-spec` for other chains than Polkadot (#1567)

* update networking types

* port over overseer-protocol message types

* Add the collation protocol to network bridge

* message sending

* stub for ConnectToValidators

* add some helper traits and methods to protocol types

* add collator protocol message

* leaves-updating

* peer connection and disconnection

* add utilities for dispatching multiple events

* implement message handling

* add an observedrole enum with equality and no sentry nodes

* derive partial-eq on network bridge event

* add PartialEq impls for network message types

* add Into implementation for observedrole

* port over existing network bridge tests

* add some more tests

* port bitfield distribution

* port over bitfield distribution tests

* add codec indices

* port PoV distribution

* port over PoV distribution tests

* port over statement distribution

* port over statement distribution tests

* update overseer and service-new

* address review comments

* port availability distribution

* port over availability distribution tests

* Augment Implementer's Guide XCMP docs

* Remove the note about the third category

* Make Cross-Chain Message Passing a h3

Co-authored-by: Sergei Shulepov <[email protected]>

* Support `build-spec` for other chains than Polkadot

The problem when building a chain specification is that you require the
native runtime to parse the json file (assuming the chain spec is not
raw yet). Before this pr we could only overwrite the native runtime when
running the node using `force_*`. This pr now adds support to load the
native runtime when the filename starts with the name of the chain. So,
when usng `build-spec --chain rococo-something-else.jon` it will use the
rococo native runtime to load the chain spec.

* Apply suggestions from code review

Co-authored-by: Andronik Ordian <[email protected]>

Co-authored-by: Andronik Ordian <[email protected]>

* master:
  impl availability distribution
  companion PR for #5732: pubsub RPC for grandpa justifications (#1346)

Closes #1237

* Companion PR for #5732

Add subscription RPC for listening on GRANDPA justifications.

* grandpa-rpc: some merge fixes

* "Update Substrate"

Co-authored-by: parity-processbot <>

* master:
  Implementer's guide: Messaging overview stub (#1405)
  Align for "Starting parachain attestation session" (#1554)

* master:
  break out subsystem-util and subsystem-test-helpers into individual crates (#1553)

* Introduce the Messaging Overview doc

* Update to the latest thinking

* break out subsystem-util and subsystem-test-helpers into individual crates

* cause all packages to check successfully

* master:
  implement provisioner (#1473)
  Implementer's guide: downward messages and HRMP, take 2 (#1503)
  Revert "Ignore checks for companion PRs (#1455)" (#1549)