Implement chain registry rpc discovery

[DavideSegullo]

I suggest implementing the chain registry to find information regarding bitsong and find the available rpc nodes to which to make requests

[angelorc]

We can add the registry as new package @bitsongjs/registry

var chain_info = registry.getChain('bitsong')
chain_info.getRandomRPC()

[angelorc]

its important to add a kind of ping before returning the endpoint

[DavideSegullo]

its important to add a kind of ping before returning the endpoint

Yes, that's why I created #10

[DavideSegullo]

I thought about it, I think it is better not to directly integrate the chain-registry, it is only redundant, we will recommend using it and we will describe it in the documentation #12

[angelorc]

Ok we can do it in a separate lib outside bitsongjs. I use the same concept with golang and it is very useful