Update binance parameters to camel case

WARNING: Breaking changes in this release

All method arguments are now camel case. The motivation here is that binance API expects camel case parameters. Updating the gem to use the same makes interpreting API errors more intuitive.

Before

Binance::Api::Order.create!(time_in_force: 'GTC', symbol: 'LTCBTC', ...)

After

Binance::Api::Order.create!(timeInForce: 'GTC', symbol: 'LTCBTC', ...)