* Replace `tokio_core` with `tokio`.
* Remove `tokio-core` and replace with `tokio` in
- `ethcore/stratum`
- `secret_store`
- `util/fetch`
- `util/reactor`
* Bump hyper to 0.12 in
- `miner`
- `util/fake-fetch`
- `util/fetch`
- `secret_store`
* Bump `jsonrpc-***` to 0.9 in
- `parity`
- `ethcore/stratum`
- `ipfs`
- `rpc`
- `rpc_client`
- `whisper`
* Bump `ring` to 0.13
* Use a more graceful shutdown process in `secret_store` tests.
* Convert some mutexes to rwlocks in `secret_store`.
* Consolidate Tokio Runtime use, remove `CpuPool`.
* Rename and move the `tokio_reactor` crate (`util/reactor`) to
`tokio_runtime` (`util/runtime`).
* Rename `EventLoop` to `Runtime`.
- Rename `EventLoop::spawn` to `Runtime::with_default_thread_count`.
- Add the `Runtime::with_thread_count` method.
- Rename `Remote` to `Executor`.
* Remove uses of `CpuPool` and spawn all tasks via the `Runtime` executor
instead.
* Other changes related to `CpuPool` removal:
- Remove `Reservations::with_pool`. `::new` now takes an `Executor` as an argument.
- Remove `SenderReservations::with_pool`. `::new` now takes an `Executor` as an argument.
* Make work-notify an optional feature
* More optional ethcore features: price-info, stratum
* Make ethcore features part of dependency instead of local features
* Put cfg gate in right location
* Feature gate register function on work-notify