Add Permissionless Asset Registry Feature

[ferrell-code]

Description

Can use native token to create an asset for use on manta pay

Makes AssetRegistryMetadata a concrete type rather than generic

Creates an additional counter NextPermissionlessAssetId so the AssetIds of permissionless asset are separate from governance ones.

closes #892

---

Before we can approve this PR for merge, please make sure that all the following items have been checked off:

• Connected to an issue with discussion and accepted design using zenhub "Connect issue" button below
• Added one label out of the L- group to this PR
• Added one or more labels from the A- and C- groups to this PR
• Explicitly labelled A-calamari and/or A-manta if your changes are meant for/impact either of these (CI depends on it)
• Re-reviewed Files changed in the Github PR explorer.

Situational Notes:

• If adding functionality, write unit tests!
• If importing a new pallet, choose a proper module index for it, and allow it in BaseFilter. Ensure every extrinsic works from front-end. If there's corresponding tool, ensure both work for each other.
• If needed, update our Javascript/Typescript APIs. These APIs are officially used by exchanges or community developers.
• If modifying existing runtime storage items, make sure to implement storage migrations for the runtime and test them with try-runtime. This includes migrations inherited from upstream changes, and you can search the diffs for modifications of #[pallet::storage] items to check for any.

[github-actions]

✅ Congestion test: 1-day congestion cost (manta-runtime) is above the target daily congestion cost

[github-actions]

⚠️ Congestion test: 1-day congestion cost (calamari-runtime) is NOT above the target daily congestion cost

[Dengjianping]

Because new extrinsic has been added to this pallet, so you have to add it to tx fee diff test.

thread 'diff_tx_fees::diff_tx_fees' panicked at 'assertion failed: `(left == right)`
  left: `9`,
 right: `8`: Please update new extrinsic here.', runtime/calamari/src/diff_tx_fees.rs:1178:9

[ferrell-code]

Because new extrinsic has been added to this pallet, so you have to add it to tx fee diff test.

thread 'diff_tx_fees::diff_tx_fees' panicked at 'assertion failed: `(left == right)`
  left: `9`,
 right: `8`: Please update new extrinsic here.', runtime/calamari/src/diff_tx_fees.rs:1178:9

Done, also changed the README for the tx fee diff test if you want to take a look at that