Upgrade to polkadot-v1.0

[ToufeeqP]

Noteworthy changes in the upstream in this upgrade:

• Removed Header and BlockNumber, Added Block as Config Parameter to frame-system (#14437)
• Removed native dispatch requirement from frame-benchmarking-cli (#14474)
• Removed/renamed CLI options and removed backward compatible HTTP server from RPC server (#13384)
• Enabled GenesisConfig in no_std in Frame (#14108)
• Used proper error types in try-runtime (#13993)
• Added serde feature flag to primitives (#13027)
• Deprecate Currency, balances::transfer, introduce holds and freezing into fungible traits in Balances pallet (#12951)
• Expose API to fetch metadata for version in Metadata v15 (#13287)
• Fix longest chain finalization target lookup (grandpa-bug on devnet) (#13289)
• Get the correct number of connected peers in SyncState (#13700)
• sc-client-db: Fix PruningMode::ArchiveCanonical (#13361)
• Runtime API refactor for block ID removal (#13255)
• Removed wasmi impl from sp-wasm-interface (#14208)
• Removed sc-consensus-uncles (#13216)

Companion PR

• Avail Core PR 41

[ToufeeqP]

Hey, overall LGTM, ggwp on that huge chunk of work.

Few points:

• Spec version should be increased
• When applying the runtime upgrade on a dev chain, i got issues decoding blocks (could be because of types needing update on the explorer OR the following point)
• Some migration some to be missing, when trying the runtime i got this errors :
  
• Tested with snapshot, live chain, try-runtime and benchmarks.

Added the FRAME pallets migrations

[ToufeeqP]

Here is the diff between this branch and KateTest network: https://pastebin.com/raw/wDGxsXnv

We need to write migrations for the following pallets:

• System
• Balances,
• ImOnline,
• NominationPools
• ElectionProviderMultiPhase
• And maybe TC and Council

Not sure how you got this list, but with reference to release v1.6.2-rc1, I have added migrations to the pallets which need the migrations. For balances pallet, substrate devs have recommended using the script which calls the extrinsic to migrate the affected storages.

[markopoloparadox]

LGTM