[Concurrent] Custom lock interface

[aary]

Provide a custom lock interface for other mutex types to use their heterogenous lock methods. For example the interface could be like

LockedData<std::vector> locked_vector;
auto lock = locked_vector.lock_custom([](auto& mtx) {
    mtx.lock_upgrade();
}, [](auto& mtx) {
    mtx.unlock_upgrade();
});

cout << lock->size() << endl;