[Core] Implement getTokenInfo on HTS to retrieve the treasury account and token info

[acuarica]

HTS allows the user to set up a treasury account which acts as the receiver when newly minted tokens are created. In order to support mint (and burn) operations¹, we need to have access to the treasury account. The treasury account² is retrievable through the getTokenInfo(address)³ as specified in HIP-514.

Implement the getTokenInfo(address) as part of HtsSystemContract. Provide the necessary slots to store the corresponding information per token, i.e., TokenInfo⁴

    struct TokenInfo {
        /// Basic properties of a Hedera Token
        HederaToken token;

        /// The number of tokens (fungible) or serials (non-fungible) of the token
        int64 totalSupply;

        /// Specifies whether the token is deleted or not
        bool deleted;

        /// Specifies whether the token kyc was defaulted with KycNotApplicable (true) or Revoked (false)
        bool defaultKycStatus;

        /// Specifies whether the token is currently paused or not
        bool pauseStatus;

        /// The fixed fees collected when transferring the token
        FixedFee[] fixedFees;

        /// The fractional fees collected when transferring the token
        FractionalFee[] fractionalFees;

        /// The royalty fees collected when transferring the token
        RoyaltyFee[] royaltyFees;

        /// The ID of the network ledger
        string ledgerId;
    }

Footnotes

1. https://github.com/hashgraph/hedera-forking/issues/78 ↩

2. IHederaTokenService.sol#L148 treasury ↩

3. IHederaTokenService.sol#L668-L674 getTokenInfo ↩

4. IHederaTokenService.sol#L173-L200 TokenInfo ↩