pandas.DataFrame.boxplot(by="class", ...) doesn't plot correctly
#### Problem description
**pandas=0.24.2**
I uploaded the jupyter notebook file on [my GitHub account](https://github.com/yuriikoval1997/pandas0.24.2-has-a-problem-with-cyrillic/blob/master/pandas%20bugs.ipynb), so here I will be short.
For some reason, pandas.DataFrame.boxplot(by="class") method doesn't work correctly with Cyrillic letters in the table.

```python
for col in list(dataSetCyrillic.columns[:-1]):
    fig, ax = pyplot.subplots(figsize=(6, 6))
    dataSetCyrillic.boxplot(column=[col], 
                        by="class", 
                        ax=ax, 
                        widths=0.5)
    tmp = map(lambda x: x.replace(" ", "\n", 1), dataSetCyrillic["class"].unique())
    ax.set_xticklabels(tmp, fontsize="20")
    ax.set_yticklabels(ax.get_yticks(), fontsize="xx-large")
    ax.set_title(label=col, fontsize="xx-large", fontstyle="oblique", fontweight="bold")
    pyplot.xlabel("")
    pyplot.suptitle("")
    fig.tight_layout()
```