Trie simplification. (#2815)

* switch to simple codec, trie broken for now

* Actualy use trie_root_noext

* align some hash, failing test on EMCH comment

* Fix trie code over layout instead of hash, revert legacy code for legacy
mainnet ??

* stub behind LayOut

* fix no_std

* temp solution for legacy trie behind feature legacy-key in various crate

* use remote project

* rc client db need prefix

* update trie deps

* bum spec runtime version

* Removing legacy as default.

* Switch mode to non legacy.

* bump runtime version

* Remove legacy trie compatibility features.

* fix warning

* bump version

* change hash on new test.

* Move dependency (#11 trie PR) patched to a parity repo.
Bench reverted to correct hasher.
Some renaming and doc improvments.

* ChildBitmap renaming to BitMap.

* Renaming of LayOut to Layout.

* formatting.

* Removing abreviation such as _ix nb_ or bm.

* Update deps and apply renaming 'Buff' -> 'Buffer'.

* Align to latest trie crates naming changes.

* Update trie dependency.

* Update trie dependency.

* change block_import test hash

* update trie deps (trie use new scale codec but it does not seems to be
an issue).

* update to use latest trie version (no mgmt of multiple radix).

* tabify

* Restoring test to 10 000.

* Use published crate, trie bench is currently down until publishing
(require another pr to update version).

* Update trie-bench.

substrate/core/state-machine/Cargo.toml

@@ -8,9 +8,9 @@ edition = "2018"
 [dependencies]
 log = "0.4"
 parking_lot = "0.8.0"
-hash-db = "0.14.0"
-trie-db = "0.14.0"
-trie-root = "0.14.0"
+hash-db = "0.15.0"
+trie-db = "0.15.0"
+trie-root = "0.15.0"
 trie = { package = "substrate-trie", path = "../trie" }
 primitives = { package = "substrate-primitives", path = "../primitives" }
 panic-handler = { package = "substrate-panic-handler", path = "../panic-handler" }
@@ -19,3 +19,6 @@ num-traits = "0.2"
 
 [dev-dependencies]
 hex-literal = "0.2.0"
+
+[features]
+default = []