Technical Committee (#3041)

* Add copy of council seats as elections module.

* Split council into collective and elections modules.

Make collective instanceable.

* Propagate changes to the runtime and fix origin/event

* insert_ref and put_ref to avoid copies.

* Add tests

* Fix up collective's tests

* One more test

* Fix elections module tests

* Missed merge line

* Minor fix

* Test fixes

* Line widths

* Line widths

* Rntime version

* Remove comment

* Deduplicate

* Bump runtime again

* Fix test

substrate/srml/support/src/traits.rs

@@ -630,3 +630,13 @@ bitmask! {
 	}
 }
 
+/// Trait for type that can handle incremental changes to a set of account IDs.
+pub trait ChangeMembers<AccountId> {
+	/// A number of members `_incoming` just joined the set and replaced some `_outgoing` ones. The
+	/// new set is thus given by `_new`.
+	fn change_members(_incoming: &[AccountId], _outgoing: &[AccountId], _new: &[AccountId]);
+}
+
+impl<T> ChangeMembers<T> for () {
+	fn change_members(_incoming: &[T], _outgoing: &[T], _new_set: &[T]) {}
+}