Aggregate all liquidity restrictions in a single place (#1921)

* Clean up session key rotation

* Fix build

* Bump version

* Introduce feature to balances.

* Move staking locking logic over to central point

* ^^^ rest

* First part of assimilation

* More assimilation

* More assimilation

* Fix most tests

* Fix build

* Move Balances to new locking system

* :q!

* Bump runtime version

* Build runtime

* Convenience function

* Test fix.

* Whitespace

* Improve type legibility.

* Fix comment.

* More tests.

* More tests.

* Bump version

* Caps

* Whitespace

* Whitespace

* Remove unneeded function.

substrate/core/state-machine/src/lib.rs

@@ -29,6 +29,7 @@ pub mod backend;
 mod changes_trie;
 mod ext;
 mod testing;
+mod basic;
 mod overlayed_changes;
 mod proving_backend;
 mod trie_backend;
@@ -37,6 +38,7 @@ mod trie_backend_essence;
 use overlayed_changes::OverlayedChangeSet;
 pub use trie::{TrieMut, TrieDBMut, DBValue, MemoryDB};
 pub use testing::TestExternalities;
+pub use basic::BasicExternalities;
 pub use ext::Ext;
 pub use backend::Backend;
 pub use changes_trie::{
@@ -625,7 +627,7 @@ where
 /// differs from previous OR config decode has failed.
 pub(crate) fn set_changes_trie_config(overlay: &mut OverlayedChanges, config: Option<Vec<u8>>, final_check: bool) -> Result<(), Box<Error>> {
 	let config = match config {
-		Some(v) => Some(changes_trie::Configuration::decode(&mut &v[..])
+		Some(v) => Some(Decode::decode(&mut &v[..])
 			.ok_or_else(|| Box::new("Failed to decode changes trie configuration".to_owned()) as Box<Error>)?),
 		None => None,
 	};