Binance integration

[timurkhafizov]

Closes #108

Changes

• [x] Add Binance API credentials to User
• [x] Add modal for Binance integration
• [x] Sync Binance orders
• [x] Sync Binance withdrawals
• [x] Sync Binance deposits

Optional

• [x] Create two different transactions for exchange - if user sells ETH for BTC we create only sell transaction for ETH, while we may want to create the second one as BTC buy as well
• [ ] Sync Binance orders in parallel, since Binance API is quite slow - this needs to be discussed since it can lead to API quota exceeding in case there is one.

[kilimchoi]

looks good to me. I'd love to hear your idea on how to do parellization

[timurkhafizov]

@kilimchoi I thought to try https://github.com/typhoeus/typhoeus adapter for Faraday

[kilimchoi]

aren't you supposed to add binance to sidekiq.yml?

[kilimchoi]

Need to special-case BCC it refers to bitcoin cash not bitconnect