Convert ipfs://CIDv0 to case-insensitive CIDv1 before making the request

[lidel]

While the ecosystem moves towards base insensitive CIDv1 in Base32,
we still have a lot of data addressed with CIDv0 (case-sensitive Base58btc).

Unfortunately, the authority component of URL entered in the address bar gets force-lowercased, which breaks the case-sensitive CIDv0 identifier:

ipfs://QmbWqxBEKC3P8tqsKc98xmWNzrzDtRLMiMPL8wBuTGsMnR → ipfs://qmbwqxbekc3p8tqskc98xmwnzrzdtrlmimpl8wbutgsmnr

This is the same problem as ipfs/ipfs-companion#1006 (more examples there).

As we've discussed today, it would be a big UX win if as part of this project we detect CIDv0 passed to ipfs:// and fix it up by converting it to case-insentive CIDv1, allowing users to load legacy CIDs.