Slash Authorities for irrefutable misbehavior (#84)

* double-commit and prepare misbehavior

* get misbehavior on completion

* collect misbehavior on drop, not only on success

* kill unused transaction_index field

* add primitive misbehavior report type

* add misbehavior report transaction

* store prior session

* fix set_items

* basic checks for misbehavior reports

* crate for substrate bft misbehavior checking

* integrate misbehavior check crate

* fix comment

* new wasm binaries

* fix hash in test

* import misbehavior transactions into queue

* fix test build

* sign on digest and full proposal when proposing

* detect proposal misbehavior

* fix fallout

* restore balance/bondage types

substrate/polkadot/runtime/src/environment.rs

@@ -31,8 +31,6 @@ pub struct Environment {
 	pub parent_hash: Hash,
 	/// The current block digest.
 	pub digest: Digest,
-	/// The current transaction index
-	pub transaction_index: u64,
 }
 
 /// Do something with the environment and return its value. Keep the function short.