cleaned up the db pdo connection and persistence dependency mess

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extra : rebase_source : 22d92647463972bf8ea9394639d8625572bf16cb
fixed type hints

--HG--
extra : rebase_source : aac9e4154c1dfaa828a592c17f67e85cc40720c9
let the container hold the registry instances, userland code used core::getXRegistry() anyway

--HG--
extra : rebase_source : 11cc97de857e590f266eb0704c40c9c5aa54b309
refactored registry tests

--HG--
extra : rebase_source : 7f816c3a65110c5d1704954506797bb52075fcd3
updated missing tests

--HG--
extra : rebase_source : 89f686713fb0c493083189d93404775e44b0d9b7