v6.5.0

• add getAccountUnit
• bridge introduces a method prepareTransaction(account, transaction): Promise<Transaction> that will complete information for the transaction to be ready. We will use that to fill the gasLimit info. In the future we can unify more stuff in that, like fetching the available fees. We will brainstorm more internally, how often we need to resync with such function / where to do it & do we need more precise lifecycles (before/after?). I think this is the most tricky UI part of our whole application because a lot of mutual dependencies between fields and behavior differences between coins.
• it also makes libcore bridge ready to use for ERC20