Fix 'dictionary changed size during iteration' error on python3.3 when using process_iter()
Fix 'dictionary changed size during iteration' error on python3.3 when using process_iter()


ERROR: test_fetch_all (__main__.TestCase)
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Traceback (most recent call last):
  File "test/test_psutil.py", line 1497, in test_fetch_all
    for p in psutil.process_iter():
  File "/home/giampaolo/svn/psutil/psutil/__init__.py", line 763, in process_iter
    for pid, proc in _pmap.items():
RuntimeError: dictionary changed size during iteration

ztop/psutil,ztop/psutil,ztop/psutil,ztop/psutil