Polkadot v0.9.1

Upgrade priority: Low (upgrade at your convenience)
Native runtimes:

• Polkadot: 9010
• Kusama: 9010
• Westend: 9010

This release was tested against the following versions of rustc. Other versions may work.

• rustc 1.51.0 (2fd73fabe 2021-03-23)
• rustc 1.53.0-nightly (7f4afdf02 2021-04-22)

WASM runtimes built with srtool using rustc 1.52.0-nightly (d6eaea1c8 2021-03-14).

Proposal hashes:

• polkadot_runtime-v9010.compact.wasm - 0x1b80c6c48d3b8692aabdb77a0a60c8dcb0f4ef7892b9734240cda82d0a8e1dbf
• kusama_runtime-v9010.compact.wasm - 0x95626a74640376c9a7c8fd64485c8edc111d6e830a4bca81d52ab0a5229ecd0f

Changes

• More secure Signed implementation (#2963)
• Initial integration of Gilts pallet (Kusama) (#2587)

Client

• Add a JSON-RPC request for reserved nodes (paritytech/substrate#8704)
• Change to use the same subcommand syntax as subkey (paritytech/substrate#8678)
• subkey: display SS58 encoding of public key (paritytech/substrate#8674)
• RPC to trace execution of specified block (paritytech/substrate#7780)

Runtime

• ✅ trivial Enable Para Registration on Kusama (#3014)
• ✅ audited Add Auctions and Crowdloans to Kusama and Westend (#2999)
• ✅ trivial Add arithmetic dispatch errors. (paritytech/substrate#8726)
• ✅ trivial primitives: remove random_seed from BlockBuilder API (paritytech/substrate#8718)
• ✅ trivial Make custom on runtime upgrade prior to pallet ones (paritytech/substrate#8687)