Adds metadata module and resolvers

[leeren]

This PR adds canonical metadata providers and makes the existing IP resolver more flexible.

The metadata provider is used for storing canonical metadata prescribed by Story Protocol, which currently includes registrant, hash, registration date, url, and name. The idea behind this PR is to decouple "rendering" from the actual metadata storage itself, and provide flexibility for allowing Story Protocol to add new fields to the canonical metadata attributes shared across all IP in the future.

On the other hand, the IP resolver is used for IP creators to provide additional flexibility in how they want their IP records to be resolved. Creators may choose to make this a custom contract, or resolve to custom key-value string records. You could imagine Disney creates a canonical DisneyResolver whose key-value pairs represent traits used across their animated series.

As such, when a registration happens, which must be done by the registration module, it will both set a metadata provider (used for Story Protocol canonical metadata storage), and an IP resolver (which by default will be set to the Story Protocol canonical IP resolver, but other periphery contracts may choose to change this to something else).

What this PR does not yet cover:

• How the protocol can support multiple IPAssetRenderers (or whether it should be allowed to at all)
• Standardization around IP resolver records (e.g. we should later add an interface resolver to support generic contract + function pairs)