feat: add the registry pkg

[AaronCQL]

Refactor of #8:

• Shifted all code to the registry pkg
• Exported names changed to the following:

  export type { ChainRegistryAssetList } from "./types/ChainRegistryAssetList";
  export type { ChainRegistryChainInfo } from "./types/ChainRegistryChainInfo";
  export type { KeplrChainInfo } from "./types/KeplrChainInfo";
  
  export { getChainRegistryAssetList } from "./apis/getChainRegistryAssetList";
  export { getChainRegistryChainInfo } from "./apis/getChainRegistryChainInfo";
  export { toKeplrChainInfo } from "./keplr/toKeplrChainInfo";

• Function signature of toKeplrChainInfo changed to:

  function toKeplrChainInfo(
    chainRegistryChainInfo: ChainRegistryChainInfo,
    chainRegistryAssetList: ChainRegistryAssetList,
    options?: {...}
  ): KeplrChainInfo

• Added script to generate the Chain Registry types

[ryoid]

lgtm