[Generation Model]: Changed sortPopulation to use merge sort
[Generation Model]: Changed sortPopulation to use merge sort

Changed sortPopulation from an O(n^2) bubble sort to an O(nlogn) merge
sort, to make it more efficient on large populations.

Signed-off-by: Sebastian Lenartowicz <82628b08c690d7b843f293282c58895740bc10b7@uoguelph.ca>

NGTOne/libHierGA