Testnet4 parameters

[mnaamani]

With Litecoin Core v0.14.2 Release Candidate Testnet3 has been deprecated and replaced with Testnet4

We will need to add new parameters to the lib/protocols/networks.js
Should we replace the existing testnet parameters or add a new testnet4?

[losh11]

Please replace testnet3. It's recommended not to use it at us if possible.

[plwalters]

I think this issue can be closed I just confirmed that it seems to be using testnet 4 now.

[tonydspaniard]

@pwkad any guidelines to make this work with testnet?