Fix Ledger and Trezor Hardware support

[chmanie]

Payout

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Description

Issue owner: raul@colony.io

The purser-ledger and purser-trezor packages do not work with current versions of the hardware. The goal is to fix support for both of these devices for message and transaction signing.

It should be possible to take the code from #271 and build on top of it.

This info from #271 might be helpful:

[...] such that the seeded signature values for the transaction to be signed (i.e. r, s and v) are not included. This is because ethereumjs-tx makes validations for EIP-155 that read these values (if present) and compare them with the chain ID, which was leading to validation errors for mainnet transactions.

This issue is regarded complete when:

• Transaction signing (via purser's sign method) and arbitrary data signing (via purser's signMessag method) work on Trezor and Ledger devices with the latest firmware.
• A test file is provided to be able to easily test this in a browser
• A video is provided showing the login process working with a Ledger and a Trezor device