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.

Describe the solution you'd like
A clear and concise description of what you want to happen.

Describe alternatives you've considered

Additional context
Add any other context or screenshots about the feature request here.

[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()