enhancement to sampleWDMass or stand-alone program to give WD cooling age and other info

[tedvh]

It would be useful for a number of projects to report not just the total age (our log(age)) at every iteration, but for WDs their cooling age. And as long as that is being calculated, it would be nice to also have the WD mass and Teff at every iteration.
*wd mass can be recalculated from ZAMS mass by calling appropriate IFMR in ifmr.c
*then calculate the age of the WD precursor with wdPrecLogAge
*cooling age is then total age - precursor age returned by wdPrecLogAge
*get Teff by calling wdMassToTeffAndRadius(double logAge, double x_carbon, double wdPrecLogAge, double wdMass, double *thisWDLogRadius)