Feature Request: Can we please have 'ema' plotting similarly to mav

[swargamr]

Is your feature request related to a problem? Please describe. I would like to plot the Exponential Moving Average in mplfinance we have Simple moving average, but ema would also help for number of stratergies.

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[alexandrepal]

Since you are dealing with DataFrames we can use something like data['Close'].ewm(span=50.0,adjust=False).mean() to get a 50 EMA. In order to plot it you can use mpf.make_addplot()