Added Opensea's Operator Filter Registry

[datboi-1337]

This makes the necessary changes to the contract to enable Opensea's new creator fee filters.

This does, of course, restrict the collections using it to only use marketplaces approved by Opensea, which I personally don't love. If we want to be able to set and collect creator fees on Opensea, however, it looks like this is the route we have to take for now.

Because the contracts provided by Opensea require 0.8.13, the compiler version has been changed here as well, and with that, comes specifying overridden contracts. Apart from that, the filter registry stuff has been imported, inherited and the transfer function overrides have been added.

[AnaTekPrimal]

This is gold, thank you.

[JohnCarp]

Hey @liarco I hope all is well!

Is there any chance you can take a look at this PR and make some suggestions? Opensea added more functions to this registry and when you try to implement it in this project there are a lot of compile errors.

I see there was a lot of discussion in the Hashlips Discord and the community really can use your help!

https://github.com/ProjectOpenSea/operator-filter-registry

    function setApprovalForAll(address operator, bool approved) public override onlyAllowedOperatorApproval(operator) {
        super.setApprovalForAll(operator, approved);
    }

    function approve(address operator, uint256 tokenId) public override onlyAllowedOperatorApproval(operator) {
        super.approve(operator, tokenId);
    }

    function transferFrom(address from, address to, uint256 tokenId) public override onlyAllowedOperator(from) {
        super.transferFrom(from, to, tokenId);
    }

    function safeTransferFrom(address from, address to, uint256 tokenId) public override onlyAllowedOperator(from) {
        super.safeTransferFrom(from, to, tokenId);
    }

    function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory data)
        public
        override
        onlyAllowedOperator(from)
    {
        super.safeTransferFrom(from, to, tokenId, data);
    }

Thank you

[datboi-1337]

I was able to get in here and update everything to be fully in compliance with Opensea's Operator Filter Registry, including the approval functions.

[JohnCarp]

I'm curious why you removed mintCompliance modifier from this function?

Also, if this is ok shouldn't you have the other require there? i.e:

function mintForAddress(uint256 _mintAmount, address _receiver) public onlyOwner { 
    require(_mintAmount > 0 && _mintAmount <= maxMintAmountPerTx, 'Invalid mint amount!');
    require(totalSupply() + _mintAmount <= maxSupply, 'Max supply exceeded!');

    _safeMint(_receiver, _mintAmount);
}

[datboi-1337]

This is unrelated to the Opernsea filter, just a general tweak that I have found people have issues with sometimes. I did briefly mention it in the push, but this change simply removes the restriction from the owner to mint more than the current maxMintAmountPerTx. It still ensures that maxSupply will not be exceeded, but allows the contract owner to mint multiple tokens, even if maxMintAmountPerTx is set to 1, for example.

[JohnCarp]

That's pretty good! Left a comment @datboi-1337