Add support for BIP39 mnemonic

[smartpunter]

Something like convertMnemonice(mnemonicPhrase, addressIndex), which takes bip39 mnemonic, converts it to proper private key, according to index, and returns both private key and NAS wallet.

addressIndex is used in BIP32 path, used for generating private key from mnemonic entropy.

This standarts are widely used in all hardware wallets, so it will come handy, adding support for them, and building interfaces to manage private keys for users.

More information:
https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki
https://github.com/bitcoin/bips/blob/master/bip-0044.mediawiki

[ChengOrangeJu]

Hello @smartpunter We are looking into your issue, stay tuned

[ChengOrangeJu]

Thank you for your information @smartpunter , that's very helpful.
After internal discussion, I found that Nebulas' standard mnemonic phrase has been merged into https://github.com/satoshilabs/slips/blob/master/slip-0044.md, the NAS index is “2718”.
Nebulas has been focus on our Incentive Program on developing DApps and resource is quite tight. The web sample may not be carried out in the near future. This issue is labelled with help wanted, and we would really appreciate the help from community. Thanks!

[ChengOrangeJu]

bounty program https://www.nebulas.io/developers.html for hardware wallet

[hostgame]

Implementation of nebulas bip32/bip39/bip44 in javascript.
iancoleman/bip39#314
P.S. It is incompatible with NAS nano pro mnemonic. This app is closed-source so I haven't opportunity to research it.