Finish migration to v2 primitives (#5037)

* remove v0 primitives from polkadot-primitives

* first pass: remove v0

* fix fallout in erasure-coding

* remove v1 primitives, consolidate to v2

* the great import update

* update runtime_api_impl_v1 to v2 as well

* guide: add `Version` request for runtime API

* add version query to runtime API

* reintroduce OldV1SessionInfo in a limited way

polkadot/node/overseer/src/lib.rs

@@ -71,10 +71,7 @@ use futures::{channel::oneshot, future::BoxFuture, select, Future, FutureExt, St
 use lru::LruCache;
 
 use client::{BlockImportNotification, BlockchainEvents, FinalityNotification};
-use polkadot_primitives::{
-	v1::{Block, BlockId, BlockNumber, Hash},
-	v2::ParachainHost,
-};
+use polkadot_primitives::v2::{Block, BlockId, BlockNumber, Hash, ParachainHost};
 use sp_api::{ApiExt, ProvideRuntimeApi};
 
 use polkadot_node_network_protocol::v1 as protocol_v1;
@@ -336,7 +333,7 @@ pub async fn forward_events<P: BlockchainEvents<Block>>(client: Arc<P>, mut hand
 /// # use std::time::Duration;
 /// # use futures::{executor, pin_mut, select, FutureExt};
 /// # use futures_timer::Delay;
-/// # use polkadot_primitives::v1::Hash;
+/// # use polkadot_primitives::v2::Hash;
 /// # use polkadot_overseer::{
 /// # 	self as overseer,
 /// #   OverseerSignal,

polkadot/node/overseer/src/tests.rs

@@ -28,7 +28,7 @@ use polkadot_node_subsystem_types::{
 	messages::{NetworkBridgeEvent, RuntimeApiRequest},
 	ActivatedLeaf, LeafStatus,
 };
-use polkadot_primitives::v1::{
+use polkadot_primitives::v2::{
 	CandidateHash, CollatorPair, InvalidDisputeStatementKind, ValidDisputeStatementKind,
 	ValidatorIndex,
 };