Remove all (non-dev) client references from frame, activate dependency enforcer (#4184)

* Move transaction pool to primitives

* move backend, errors into primitives

* remove unused client depencies

* Move rpc-api into primitives

* Move peerset back to client

* Move rpc/api back to client, move palette/support/rpc into utils

* move support-rpc into subfolder

* move system-rpc into utils

* move transaction-pool  and -graph back into client

* fix broken imports

* Clean up test primitives

* Make support test utils independent of frame

* remove unnecessary node dependencies from service

* Reactivate dependency script:
 - only enforce the now achieved status quo will remain
 - allow for primitives to depend on /client for now without failing
 - more discriptive error message so people understand, what it wants
 - minor fix to differentiative between ../client and /client (which may be a subfolder)
 - don't allow this to fail anylonger.

* fix doc comment

* 'Should not' rather than 'must not'.

* Revert unwanted dependency changes

* fix faulty import

* fixup derive_more version

* fix wrong import path

substrate/client/finality-grandpa/src/consensus_changes.rs

@@ -47,11 +47,11 @@ impl<H: Copy + PartialEq, N: Copy + Ord> ConsensusChanges<H, N> {
 
 	/// Finalize all pending consensus changes that are finalized by given block.
 	/// Returns true if there any changes were finalized.
-	pub(crate) fn finalize<F: Fn(N) -> ::client_api::error::Result<Option<H>>>(
+	pub(crate) fn finalize<F: Fn(N) -> ::sp_blockchain::Result<Option<H>>>(
 		&mut self,
 		block: (N, H),
 		canonical_at_height: F,
-	) -> ::client_api::error::Result<(bool, bool)> {
+	) -> ::sp_blockchain::Result<(bool, bool)> {
 		let (split_idx, has_finalized_changes) = self.pending_changes.iter()
 			.enumerate()
 			.take_while(|(_, &(at_height, _))| at_height <= block.0)