account splits the key space into independent user identities
address_index is used as child index in BIP32 derivation
change is a constant used for public derivation. Constant 0 is used for external chain and constant 1 for internal chain.
coin_type is a constant that improves privacy
purpose is a constant set to 44' (or 0x8000002C) following the BIP43 recommendation
BIP44Params is used as path field in ledger item in Record.