Create project registry

[mzxyz]

Changes

• Create ProjectRegistry contract
• Support NFT features for ProjectRegistry
• Remove unused functions

[ianhe8x]

We can consider to support The enumeration extension is OPTIONAL for ERC-721 smart contracts (see “caveats”, below). This allows your contract to publish its full list of NFTs and make them discoverable.
https://eips.ethereum.org/EIPS/eip-721

[ianhe8x]

@mzxyz have you added the change to merge indexing with ready?
also the change to allow indexer stop receiving new agreement

[mzxyz]

@ianhe8x In Solidity, when using super with multiple inheritance, the function calls are determined by the C3 linearization of the inheritance graph (or the C3 superclass linearization). In practice, it means that when you use super, the function that gets called is the next one in line based on the linearized order of inheritance, starting from the current contract and moving right to left through its base contracts. Once it finds and executes a matching function in this order, it stops.

https://docs.soliditylang.org/en/develop/contracts.html#multiple-inheritance-and-linearization