Mesh 2176/fix-storage-naming

[HenriqueNogara]

changelog

modified external API

• Deprecate the following asset storage: AssetMetadataNextLocalKey, AssetMetadataNextGlobalKey;
• Deprecate the following NFT storage: NextCollectionId, NextNFTId;

new external API

• Add the following asset storage: CurrentAssetMetadataLocalKey, CurrentAssetMetadataGlobalKey;
• Add the following NFT storage: CurrentNFTId, CurrentCollectionId;

data migration

• Initializes new storage for the asset pallet;
• Initializes new storage for the nft pallet;