follow-chain testing mode for try-runtime (and revamp CLI configs). (#9788)

* deadlock, need to ask someone to help now

* Finally it seems to be working.. at least for a few blocks

* self-review

* major mega revamp

* some small fixes

* another mega refactor

* add license

* Apply suggestions from code review

* hack around signature verification

* Some fixes

* Update utils/frame/try-runtime/cli/src/lib.rs

Co-authored-by: Zeke Mostov <32168567+emostov@users.noreply.github.com>

* Update utils/frame/try-runtime/cli/src/lib.rs

Co-authored-by: Zeke Mostov <32168567+emostov@users.noreply.github.com>

* Update utils/frame/try-runtime/cli/src/lib.rs

Co-authored-by: Zeke Mostov <32168567+emostov@users.noreply.github.com>

* final tweaks, hopefully.

* a little self-review

* Add the ext root check

Co-authored-by: Zeke Mostov <32168567+emostov@users.noreply.github.com>

substrate/utils/frame/try-runtime/cli/src/commands/mod.rs

@@ -0,0 +1,21 @@
+// This file is part of Substrate.
+
+// Copyright (C) 2021 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+pub(crate) mod execute_block;
+pub(crate) mod follow_chain;
+pub(crate) mod offchain_worker;
+pub(crate) mod on_runtime_upgrade;