Create SimulatePop_NeutralLocus_Biallelic

Code to simulate a neutral, biallelic locus in a diploid population through time.  Has the option to take samples at two time points: the end (end at time t = # generations + length of interval) and an intermediate time point (at time t = # gens).   Run the code by simply editing the parameters at the bottom of the file, and add desired file name.