Bringing in basic CUDA files
Adapting makefile. More changes needed
Convenience typedefs for Eigen
Eigen types defined and replaced in driver and EMFields
CUDA implementation plan
Drafted all fixed-sized eigen objects version
Fixed model base class to be guiding center class
Changed to RungeKutta4
Missing space before boost flags
Added GC_DIM macro and declared em_fields and model to be not pointers.