fix bug which do not transform bitmap with exif rotation on default setting

`BitmapHunter` should transform bitmap automatically with rotation information on EXIF when `exifRotation` is not 0. But in original `BitmapHunter`, don't executes transform operation if `data.needsTransformation()` is `false`, even if `exifRotation` is not 0. So condition of the if statement should `data.needsTransformation() || exifRotation != 0`, not `data.needsTransformation()` only.