Update to work with latest js-ipfs-http-client

[lidel]

@SgtPooki noted that this library does not work with the latest version of https://www.npmjs.com/package/ipfs-http-client.

👉 We need ipfs-geoip to work with the latest ipfs-http-client so we can use it in ipfs-webui and have no regressions on Peers screen.

Some thoughts:

• I suspect main issue is that we removed Buffer in JS libs and use Uint8Array
• some useful libs:
  • https://www.npmjs.com/package/uint8arrays
  • https://github.com/alanshaw/it-awesome
• modern JS API is documented at https://github.com/ipfs/js-ipfs/tree/master/docs/core-api

[lidel]

This is no longer a concern – #93 introduced support for fetching raw blocks from Gateways and a custom block getter function.