Assign unique storage names to pallets. (#5010)

* Assign unique storage names to pallets.

* Bump spec

* Upgrade logic for finality tracker (untested)

* Logic for migrating Identity (untested)

* Logic for migrating transaction-payment

* Fix tests

* Fix `decl_storage` build

* Contract -> Contracts

* Update Cargo.lock

* bump spec

* update migration

* Fix merge error

* Migration for contracts

* Remove serde

* Remove some illegal spaces and Options

* Fix types in identity.

* Minor variable rename

Co-authored-by: Gavin Wood <gavin@parity.io>

substrate/frame/example/src/lib.rs

@@ -326,6 +326,10 @@ decl_storage! {
 	// A macro for the Storage trait, and its implementation, for this pallet.
 	// This allows for type-safe usage of the Substrate storage database, so you can
 	// keep things around between blocks.
+	//
+	// It is important to update your storage name so that your pallet's
+	// storage items are isolated from other pallets.
+	// ---------------------------------vvvvvvv
 	trait Store for Module<T: Trait> as Example {
 		// Any storage declarations of the form:
 		//   `pub? Name get(fn getter_name)? [config()|config(myname)] [build(|_| {...})] : <type> (= <new_default_value>)?;`