Display properly RGB images having Planar Configuration = 1

I have made some changes in order to take into account the byte ordering in RGB images for any Planar Configuration value (issue #31). Screenshot attached.

You should add the necessary code to read and store the value of that Dicom Element (0028, 0006).

 José Antonio

![RGB_PlanarConfiguration_1](https://f.cloud.github.com/assets/929672/452852/773bcc22-b2fe-11e2-8585-648bfba95995.png)