Simple program showing how to use get_seconds from the igl library

Compile with:
  make

Run with:
  ./example
which should produces something similar to:
  start: 0.001414s
  1.00141s - 0.001414s = 1s
  2.00141s - 0.001414s = 2s
  3.00142s - 0.001414s = 3s
  4.00141s - 0.001414s = 4s
  5.00141s - 0.001414s = 5s
  6.00141s - 0.001414s = 6s
  7.00141s - 0.001414s = 7s
  8.00141s - 0.001414s = 8s
  9.00141s - 0.001414s = 9s
  10.0014s - 0.001414s = 10s
  end: 10.0014s
