add benchmark printout ordering feature

[baltzell]

This new sortByName() overwrites its Benchmark's LinkedHashMap<String,BenchmarkTimer> storage container, to achive two things for printing:

1. deterministic order, based on String naturals
2. put some "special" keys at the beginning

For this to have any effect, one needs to call sortByName before printing. Could instead have different benchmarks with different automatic sorting. Currently the default ordering is the call order, which is a good default and what you want for serial stuff.