[Wallet] Sign transaction module

[flexsurfer]

Implement a new module, it should

• get tx data map on input
• show title (1)
• show tx details on the bottom sheet (details should be different for sending eth or calling contract (2))
• it's only possible to change one field - network fee in this module
• sign with password
• show sent popup

this issue doesn't include:

• USD values (3) [Wallet] Show values in the user's currency #8027
• sent popup design [GHI]
• tx fee slider [GHI]
• to field details [GHI]
• approveAndCall detection (showing token amount) [GHI]
• prompts for signing phrase, gas and gas price [GHI]

[rachelhamlin]

Notes from 8/5/2018 call:

• Keeping signing phrase, not using emoji guard.
• Overview screen can not be edited by the user in first iteration.
• Cancel brings user back to the screen where Tx was initiated: from wallet, to the input fields. From DApp, to the screen that launched Tx. From chat, back to chat.
• Confirmation pop-up appears over Tx launch screen (e.g. DApp).
• Token amount can display as N/A if the Tx is only for gas.
• New Data field will contain other information from the Tx, such as a TtT setting amount. For non-Status contracts, this data will not be human readable. Requires more effort. Power users appreciate seeing it. For Status contracts, we could make the data readable.
• Not using Wallet field until we have multi-account.
• Not using the DApp field in first iteration. In future, could pull the URL from the browser if Tx was launched there.
• Not including conversion rates in first iteration. In future, must decide how many decimal points to show.
• Passcode / pincode / Keycard sign are all required. First iteration can probably get away with passcode only, as pincode/Keycard are not in production yet.
• QA is concerned about overflow on certain lines, e.g. if translated to different language or long network fee.

Design changes needed

• A way to see full recipient address, either in a dedicated field or on a long press.
• Error state in place of confirmation screen, to be used if Tx fails because user does not have enough ETH/token
• Info button/tool tip with copy explaining what signing phrase does
• Slight variation of overview screen required for signing messages that don't have on-chain Tx (e.g. logging in): "Signing message" vs. "Signing transaction" and only the recipient and signing phrase fields are necessary.

[flexsurfer]

take this into account:
eth_signTypedData_v3 password is refused. #8241
web3.personal.sign() not displaying message to sign and refusing password #8209
Gas estimation on contract transfers for Eth transfers incorrect #8269