Lisk Element should allow BIP39 standard passphrase with up to 24 words

[reyraa]

Expected behavior

• Since the BIP39 standard allows to generate a passphrase with up to 24 words and since we use mnemonic which implements this standard, we should not allow users to use passphrases longer than 12 words. This includes generation and validation.
  One option would be to let people pass the number of words they want to get from the passphrase generator module.

Actual behavior

Currently, the passphrase is limited to 12 words. This seems to not be a technical restriction, but more of a business decision.

Which version(s) does this effect? (Environment, OS, etc...)

• Version 1.1.2 and before