[ethcore]: apply filter when PendingSet::AlwaysQueue in ready_transactions_filtered (#11227)

* [ethcore]: apply filter when `from_queue`

In `ready_transactions_filtered` the filter were never applied when
the options PendingSet::AlwaysQueue` was configured which this fixes

It also adds a two tests for it

* [ethcore test-helpers]: stray printlns

* docs(ethcore filter options): more generic desc

* tests(ethcore miner): simply filter tests

* [ethcore filter_options]: fix nits

* doc: nit

Co-Authored-By: David <dvdplm@gmail.com>

* doc: nit

Co-Authored-By: David <dvdplm@gmail.com>

* doc: nit

Co-Authored-By: David <dvdplm@gmail.com>

* doc: nit

Co-Authored-By: David <dvdplm@gmail.com>

* doc: nit

Co-Authored-By: David <dvdplm@gmail.com>

* doc(miner filter): simplify documentation

* [rpc]: make tests compile

rpc/src/v1/tests/helpers/miner_service.rs

@@ -229,8 +229,23 @@ impl MinerService for TestMinerService {
 		self.queued_transactions()
 	}
 
-	fn ready_transactions_filtered<C>(&self, _chain: &C, _max_len: usize, _filter: Option<FilterOptions>, _ordering: miner::PendingOrdering) -> Vec<Arc<VerifiedTransaction>> {
+	fn ready_transactions_filtered<C>(
+		&self,
+		_chain: &C,
+		max_len: usize,
+		filter: Option<FilterOptions>,
+		_ordering: miner::PendingOrdering
+	) -> Vec<Arc<VerifiedTransaction>> {
 		self.queued_transactions()
+			.iter()
+			.cloned()
+			.filter(|tx| {
+				filter.as_ref().map_or(true, |filter| {
+					filter.matches(tx.signed())
+				})
+			})
+			.take(max_len)
+			.collect()
 	}
 
 	fn pending_transaction_hashes<C>(&self, _chain: &C) -> BTreeSet<H256> {