[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 <[email protected]>

* doc: nit

Co-Authored-By: David <[email protected]>

* doc: nit

Co-Authored-By: David <[email protected]>

* doc: nit

Co-Authored-By: David <[email protected]>

* doc: nit

Co-Authored-By: David <[email protected]>

* doc(miner filter): simplify documentation

* [rpc]: make tests compile

Author: niklasad1