[Mining] Tari Mining

[tarnas14]

• Tari Mining box on the Mining page
• "Set your own Tari Wallet password" <inline>
• setup the backend with tari wallet pass, call the backend, start mining (Start tari dockers through backend #61)
• "XXXX XTR" is the amount of XTR mined during current session
• while balance of mined blocks is 0, show spinning loading indicator on the left of 0000 TR

to discuss with @tari

• we don't want to store the wallet password in the frontend application state
• we need an endpoint from tari backend to store and retrieve state securely between application runs