Date picker format issues

### Description

If I try to give _format_ prop in the date picker component, the month name gets converted to chinese character.

### Reproduce Steps

1. format="dd-MMM-yy" should give **12-Aug-19** but instead it gives **12-八月-19**
2. format="dd-MMMM-yyyy" should give **12-August-2019** but instead it gives **12-8 月-19**

### Exact code I'm using
```

```