cts params evolve, GA returns all fitnesses

now continuity parameters are also subject to mutation and crossover (by
averaging).  GA returns a matrix of fitness values, for each individual
in each generation (pop size by num gens)
GeneticProgrammer

try to increase diversity??
top_half_selection added
added introduction of new members
permuted after adding new members
gaussian mutate
ga for lambda
periodic boundary condition function
testing changes
master merge