Blind Spots in Gujarati and Oriya

Hello!

I am encountering some blind spots where the result is empty.

### Examples
* GU: ૐ
* OR: ୱ୍ୱି and ଵୀ

```
from indictrans import Transliterator
trn = Transliterator(source='ori', target='eng', build_lookup=True)
trn.transform('''ୱ୍ୱି''')
```

I am not sure if the first example is really GU, but I think the second OR example is valid.

Any solution?

Thanks!

