Minute Bar Stream Source

In this release we add minute aggs as a data stream source (5dcbddd).
So now the user could select:

• Quotes
• Minute bars
  as a stream source. User could also resample for other time frames.

Minor additions/fixes:

• update the example code to only use live bars (112e4be)
• stop orders don't need limit price (919d7ec)
• don't fail if missing bars from the backfill frames (650680d)
• better error notification when order rejected (abe23b0)
• polygon data backfill fix (a7b9911)
• use today's data for intraday granularity (7210594)
• time zone issue in backfill (4890677)

Updates:

• trading calendars: 2.1.1
• alpaca_trade_api: 0.52.0