message: Add some detail to the release notes about the metadata versioning
diff: @@ -70,6 +70,16 @@ scale-info = { version = "1.0", default-features = false, features = ["derive"],
  scale = { package = "parity-scale-codec", version = "2", default-features = false, features = ["derive", "full"] }
  ```
  +### New metadata format
  +
  +There are breaking changes to the metadata format in this release.
  +
  +- Removes top level `metadataVersion` field from the contract metadata (https://github.com/paritytech/cargo-contract/pull/342/files).
  +- Introduces new top level versioned metadata [enum](https://github.com/paritytech/ink/blob/master/crates/metadata/src/lib.rs#L68).
  +- Upgrades to `scale-info` version `1.0` (https://github.com/paritytech/ink/pull/845).
  + - The previous supported version was `0.6`, so check release notes for all changes since then: https://github.com/paritytech/ink/pull/845
  + - One of the main changes to be aware of is the change to 0 based type lookup ids: https://github.com/paritytech/scale-info/pull/90
  +
  ## Added
  - Added an Ethereum-compatibility function to recover a public key from an ECDSA signature and message hash - [#914](https://github.com/paritytech/ink/pull/914) (thanks [@xgreenx](https://github.com/xgreenx)).
  - Added new utility proc. macros to `ink_lang` crate - [#947](https://github.com/paritytech/ink/pull/947):
  