* Parachains double vote handler initial implementation.

* Make tests test the actual slashing.

* Implement SignedExtension validation of double vote reports.

* Fixes build after merge

* Review fixes

* Adds historical session proofs

* Review fixes.

* Bump runtime spec_version

* Get the session number from the proof

* Check that proof matches session

* Change signature type on DoubleVoteReport

* Adds docs and removes blank lines

* Removes leftover code

* Fix build

* Fix build after a merge

* Apply suggestions from code review

Co-Authored-By: Robert Habermeier <rphmeier@gmail.com>

* Prune ParentToSessionIndex

* Remove a clone and a warning

Co-authored-by: Robert Habermeier <rphmeier@gmail.com>
Co-authored-by: Gavin Wood <gavin@parity.io>

* Updates for the new democracy

* Introduce progressive democracy

Also move to "master" branch of Substrate ready for continuous
sync with Substrate master.

* Remove migration code.

* Bump Substrate

* Bump runtime

* bump version to v0.7.27

* update to latest substrate polkadot-master

* bump runtime impl_version

* Refactor storage of various modules.

* The real list of claims

* Migration away from opaque maps

* Fix

* Fix for task executor API change

* Flag to force kusama runtime

* Chainspecs for kusama

* Polkadot config for westend

Co-Authored-By: Bastian Köcher <bkchr@users.noreply.github.com>

* 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 <arkady.paronyan@gmail.com>
Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>
Co-authored-by: Max Inden <mail@max-inden.de>

* Copy over files

* Most network tests work

* Fix copyrights

* Strip out unneeded pallets

* Update test-runtime and remove unused network test things

* Upgrade test runtime

* Strip more things out of the test runtime

* Bump kusama impl version