Add partition function to be used by quicksort
Use sort_fn_size variable instead of hardcoded value
Add insertion sort to sort test program

Not sure how it was missing
Fix formatting for sort output titles

It's a bit of a hack, but adding some spaces fixes the output just fine!
Implement quicksort for integer array
Tweak sort benchmark values

This should better show the growth of various sort functions over time
Merge branch 'quicksort'