toString to return the cid v1 string form by default?

[olizilla]

I'm upgrading a module that used the old peer-id library which would return the CID v1 string format by default

https://github.com/libp2p/js-peer-id/blob/869bb227a611722fc19b4db031c448ed926e145c/src/index.js#L158-L169

while the default here is to return the older form, and you have to call .toCID().toString() to get the same behaviour.

I suspect folks (like me) wont think to do until they finally hit an interop test that fails. I hit this while working on encoding IPNI advertisements and only found the issue once I tried to figure out why a parity test with an existing advertisement was failing.