BUG: ensure perf stats are generated for all days

When running with minutely emissions the simulator would report to the
user that it simulated 'n - 1' days (where n is the number of days
specified in the simulation params).  Now the correct number of trading
days are reported as being simulated.

zipline/algorithm.py

@@ -59,6 +59,7 @@ DEFAULT_CAPITAL_BASE = float("1.0e5")
 
 
 class TradingAlgorithm(object):
+
     """
     Base class for trading algorithms. Inherit and overload
     initialize() and handle_data(data).
@@ -83,6 +84,7 @@ class TradingAlgorithm(object):
     stats = my_algo.run(data)
 
     """
+
     def __init__(self, *args, **kwargs):
         """Initialize sids and other state variables.
 
@@ -228,7 +230,8 @@ class TradingAlgorithm(object):
         """
         if self.benchmark_return_source is None:
             env = trading.environment
-            if self.data_frequency == 'minute':
+            if (self.data_frequency == 'minute'
+                    or sim_params.emission_rate == 'minute'):
                 update_time = lambda date: env.get_open_and_close(date)[1]
             else:
                 update_time = lambda date: date