Feature Request:addplot does not take dataframe index

Nessuno ha ancora preso questa issue.

I would like to plot two data as below.

```
plot2 = mpf.make_addplot(data2, type='candle')
mpf.plot(data, type='candle', addplot=plot2)
```

However, the problem is that data2 contains 3 candles and data contains 4 candles with different indices.

data2.index
`['2021-01-05', '2021-01-06', '2021-01-07']`

data.index
`['2021-01-04', '2021-01-05', '2021-01-06', '2021-01-07']`

Despite the fact that the time index of data2 starts from 2021-01-05, the plot starts from 2021-01-04
You can see three overlapped candles on 01-04, 01-05, 01-06.

Please allow addplot to have its own x values as the index of the input dataframe.

Start by reproducing the reported example with mpf.make_addplot() and mpf.plot(), using the two dataframes and their differing indices. Inspect how addplot data is positioned relative to the main plot's x values. Done means addplot uses its input dataframe index so the three candles align with 2021-01-05 through 2021-01-07 rather than starting at 2021-01-04.

Scritto dal modello di indicizzazione a partire dal testo della issue.