concepts.currency: fix prints for python < 2.7
concepts.market.Ticker.RATE_FIELDS
Start on Bitstamp support.
Try to implement the getOpenTrades() function.
bitstamp corrections
bitstamp small bug
bitstamp: prevent current getOpenTrades() usage
give all datetimes in UTC
concepts.currency.ExchangeRate.by(). Simplified implementation
concepts.currency.ExchangeRate. Expose properties, new docstrings
disambiguate market.currency1/2 into buy/sell_currency. Define them, expose them as properties, docstrings
concepts.numpy_conversions
new util.monitor, demo