Outdated btcd/btcec dependency

[fuddin95]

Due to outdated dependecies, it fails to install the main go-hdwallet repositry. The cause of this issue stems from github.com/btcsuite/btcd/btcec/ which doesn't exists anymore. This repository is now updated and can be installed using $ go install -u -v github.com/btcsuite/btcd/btcec/v2

At the current stage this repository is not usable since, it doesn't even compile.

If you would like, I can open a pull request addressing these issues