References for data used in current DOLPHOT module

- Zero Points: http://purcell.as.arizona.edu/wfpc2_calib/ (2009 May 13)
- Encircled Energy: implicit in zero points, which are computed to 0.5" radius
- CTE Corrections: http://purcell.as.arizona.edu/wfpc2_calib/ (2009 May 13)
- PSFs: Tiny Tim 7.0
- Distortion Coefficients: Holtzman et al. (1995), PASP, 107, 156
- Pixel Area Map: Computed from distortion coefficients
