Add dimension order methods with corresponding unit tests
Create isValidImageIndex method including the image count check
Add getPixelsSize() method
Create generic setImageProperty() getImageProperty() functions
Rename type and dimensions order methods to stick to the model methods
Refactor the metadata image property unit testing

- Create TestImageProperty interface
- Move PixelsDimensionOrder and PixelsType test to their respective test cases
Add setPixelsSize/getPixelsSize methods with their corresponding tests