rename polkadot-collator to polkadot-parachain (#1241)

* rename polkadot-collator to polkadot-parachain

Not every node has to be a collator.

* Update README.md

Co-authored-by: Chevdor <[email protected]>

* rename docker file

* Update .github/workflows/extrinsic-ordering-check-from-bin.yml

Co-authored-by: Chevdor <[email protected]>

* Versioning scheme that tracks polkadot relay chain

but allows for patch releases by having a 0 at the end.
(`-patch1` patch naming schemes were discussed but they
were judged to cause downstream packagers pain.)

* update name

* update lock file

Co-authored-by: Chevdor <[email protected]>