Assignment 2
Gavin Li and Linda He

Platforms: Linux and Mac

Required Features:
- transformations for both geometry and lights+camera
- spheres and triangles and .obj
- basic phong shading
- lighting and shadows
- outputs as png
  - set image size with -w and -h options
  - set output file name with -o option
- .rti file(s) are positional command line arguments

Extra Features:
- bounding box test for .obj files
- transparency + refraction
  - extra optional params for mat: <refrR> <refrG> <refrB> <refrIndex>
- extra robust against errors in .rti files