docs: Add link to Java Libraries with Hashing Function to README

[vorburger]

I am using Multihash in (my) dev.enola.common.io.hashbrown.Multihashes class, but so far was only able to "map" 3 of the (many) Type of Multihash to hashing functions of which I actually have a (Java) implementation...

Would it perhaps make sense to have a section in the README listing recommended (other) libraries which support (some of) all these has functions?

I could raise a PR to make a start with the Guava com.google.common.hash mapping, if that would be of interest? Does anyone reading this have pointers to others?

Or... should this perhaps not be "doc", but "code" - would (something like) my utility class be useful in this java-multihash project itself? But then it would depend on other libraries. Or should we create a new repo under multiformats for this?

[ianopolous]

This is definitely trying not to depend on any hash implementations, as consumers of this library can use different implementations for different reasons. Many users also won't be interested in most of the hash functions.

[vorburger]

This is definitely trying not to depend on any hash implementations, as consumers of this library can use different implementations for different reasons. Many users also won't be interested in most of the hash functions.

@ianopolous ACK; that makes perfect sense. In that case, how about #42 just as an (initial) doc - merge?

PS: If you or anyone else reading this has pointers to other libraries implementing any of the Multihash functions, contrib. PRs adding them to the README!