prepping for releasing rc6 (#6922)

* Bump version

* update test-utils crates to be ready for publishing

* adding changelog

* Adding automaticly generated READMEs

* fixing versions

* another version mishap

substrate/client/basic-authorship/README.md

@@ -0,0 +1,32 @@
+Basic implementation of block-authoring logic.
+
+# Example
+
+```rust
+// The first step is to create a `ProposerFactory`.
+let mut proposer_factory = ProposerFactory::new(client.clone(), txpool.clone(), None);
+
+// From this factory, we create a `Proposer`.
+let proposer = proposer_factory.init(
+	&client.header(&BlockId::number(0)).unwrap().unwrap(),
+);
+
+// The proposer is created asynchronously.
+let proposer = futures::executor::block_on(proposer).unwrap();
+
+// This `Proposer` allows us to create a block proposition.
+// The proposer will grab transactions from the transaction pool, and put them into the block.
+let future = proposer.propose(
+	Default::default(),
+	Default::default(),
+	Duration::from_secs(2),
+	RecordProof::Yes,
+);
+
+// We wait until the proposition is performed.
+let block = futures::executor::block_on(future).unwrap();
+println!("Generated block: {:?}", block.block);
+```
+
+
+License: GPL-3.0-or-later WITH Classpath-exception-2.0