Options trading backtest fails

[adamjbradley]

A comparison of a str and float64 resulted in an error. Fixed by casting to a float!
backtesting_broker.py line 446:

    # Calculate profit/loss per contract
    # TODO AJB cast position.asset.strike to float (was a string)
    if position.asset.right == "CALL":
        profit_loss_per_contract = underlying_price - float(position.asset.strike)
    else:
        profit_loss_per_contract = float(position.asset.strike) - underlying_price