Closed Unassigned: Unable to create/write EXIF data. [1272]

Taking an image (in this case it's already been resized to a progressive JPEG and had existing EXIF stripped). The .SetValue() function triggers the exception below. Is this function being used correctly? It was intended to create the profile and then use image.AddProfile() to attach it.

Running:

```
var newExifProfile = image.GetExifProfile();
if (newExifProfile == null)
{
newExifProfile = new ExifProfile();
}
newExifProfile.SetValue(ExifTag.Copyright, "test");
```

Gives exception:
```
Object reference not set to an instance of an object.
at ImageMagick.ExifReader.GetBytes(UInt32 length)
at ImageMagick.ExifReader.Read(Byte[] data)
at ImageMagick.ExifProfile.SetValue(ExifTag tag, Object value)
```
Comments: Resolved with changeset 34758: Fixed bug in ExifProfile.