ToBitmap() - datatype mistmatch

I tried to convert a numsharp array with integers to bitmap.

```
array_rgb_numsharp = array_rgb_numsharp.reshape(1, 300, 300, 3);
Bitmap image = array_rgb_numsharp.ToBitmap();
```
and encounter this error:
System.InvalidCastException: 'Unable to perform CopyTo when T does not match dtype, use non-generic overload instead.'

How can I fix it?
