* Flag to force kusama runtime

* Chainspecs for kusama

* Polkadot config for westend

Co-Authored-By: Bastian Köcher <[email protected]>

* network/src/legacy/gossip: Wrap GossipEngine in Arc Mutex & lock it on use

`GossipEngine` in itself has no need to be Send and Sync, given that it
does not rely on separately spawned background tasks anymore.
`RegisteredMessageValidator` needs to be `Send` and `Sync` due to the
inherited trait bounds from implementing `GossipService`. In addition
`RegisteredMessageValidator` derives `Clone`. Thereby `GossipEngine`
needs to be wrapped in an `Arc` and `Mutex` to keep the status quo.

* Needed fixes.

* Fixes

* Fixed build

* Fixed build w benchmarking CLI

* Fixed building tests

* Added --dev shortcut

Co-authored-by: arkpar <[email protected]>
Co-authored-by: Bastian Köcher <[email protected]>
Co-authored-by: Max Inden <[email protected]>