Implement EVM Address Type into HDWallet

[eric-volz]

What to do:

It should be possible to derive a ETH Address from the given mnemonic seed and private key

Whats the problem:

Defichain uses a different algorithmus to create the main seed from the mnemonic seed.
Bacause of that feature cannot build on the foundation of the current HDWallet implementation

Steps:

• Research
• Implementation
• Tests