Add ioPay wallet

[chen-yijiang]

Hi, Team Solana-Labs,

This PR #1017 adds ioPay wallet to the list of supported wallets to make it easier for our users to connect to wallet-adapter dapps.

Please let me know if anything needs to be added or changed to satisfy your requirements.

Cheers,
ioPay Wallet team

@ssamkkim

[jordaaash]

We aren't accepting new adapters for injected wallets. See the guide for wallets. You'll want to implement the Wallet Standard in your wallet and register it as a Standard Wallet. When you do, it will be detected automatically by Solana apps that use Wallet Adapter.