Performance Test Program for Safecopy and Safemap

How to run
==========

  1. Set USE_COW_SAFECOPY to 1 or 0 in kernel/system/do_safecopy.c
     to run safecopy tests with or without COW optimization.
  2. Type `make run` to prepare and run tests. Configuration parameters
     for performance tests are in ./run.
  3. When done testing, type `make clean` to clean up.

