Experimental IW/MW2019 Normal Map Fix, Cast Processor, Merge RGB/A

• Added experimental fix for IW/MW2019 normal maps, good results across models, but keep in mind the conversion was derived from examining normal maps in Bo3/Ghosts that were loaded in MW, so probably not correct, but produces good results
• Added Merge RGB/A (image + _alpha)
• Added a Cast Processor, a requested feature made for people working with Apex Legends' assets, but will work for any cast files that contain the necessary data. It copies and renames the images for each material to their own folder with the name of the material + the name of the image slot to match the behavior of Porter's cast plugin (the name it applies to the image nodes in Maya). Note you need to export the models in Legion as "Cast" to use this with Apex Legends.
• Image output format is now saved across sessions, another feature request

Enjoy!