Transfer Polkadot-native assets to Ethereum (#5546)

# Description

Adding support for send polkadot native assets(PNA) to Ethereum network
through snowbridge. Asset with location in view of AH Including:

- Relay token `(1,Here)`
- Native asset `(0,[PalletInstance(instance),GenereIndex(index)])`
managed by Assets Pallet
- Native asset of Parachain `(1,[Parachain(paraId)])` managed by Foreign
Assets Pallet

The original PR in https://github.com/Snowfork/polkadot-sdk/pull/128
which has been internally reviewed by Snowbridge team.

# Notes

- This feature depends on the companion solidity change in
https://github.com/Snowfork/snowbridge/pull/1155. Currently register PNA
is only allowed from
[sudo](https://github.com/Snowfork/polkadot-sdk/blob/46cb3528

/bridges/snowbridge/pallets/system/src/lib.rs#L621),
so it's actually not enabled. Will require another runtime upgrade to
make the call permissionless together with upgrading the Gateway
contract.

- To make things easy multi-hop transfer(i.e. sending PNA from Ethereum
through AH to Destination chain) is not support ed in this PR. For this
case user can switch to 2-phases transfer instead.

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Co-authored-by: Clara van Staden <claravanstaden64@gmail.com>
Co-authored-by: Alistair Singh <alistair.singh7@gmail.com>
Co-authored-by: Vincent Geddes <117534+vgeddes@users.noreply.github.com>
Co-authored-by: Francisco Aguirre <franciscoaguirreperez@gmail.com>
Co-authored-by: Adrian Catangiu <adrian@parity.io>