Bullish Engulfing Backtest

This is a bullish reversal pattern formed by two candlesticks. Following a downtrend,
the first candlestick is a down candlestick which is followed by an up candlestick
which has a long real body that engulfs or contains the real body of the prior bar.
The Engulfing pattern is the reverse of the Harami pattern.

WARNING:
- For purpose educate only
- This script to change bars colors.