Sync processutils from oslo code

Sync openstack/common/processutils.py:
    cdcc19c1d78a4a88daabfb64b27abd4924aa442d
    2a4d15dda6f2c32cce322d82f1a81de6b50853f0
    8a0f5678485076fbe0ea1f318c7fd49bac3f1df8
    51778f9eef2dd88a949679f0280f69ee99fd5567
    fcf517d72cb81f972fad20caa9ff0341e9b4aa9c
    af4159266f6e366a3cd7366a672f8f8b38a2f0f2
    f773ea298cd9f322023b91247e688726cf674cd5
    8b2b0b743e84ceed7841cf470afed6a5da8e1d07
    3b71f46628822c74c66d37cae8eca9e7d8679d0d
    12bcdb71ffbe9ee1688beed1f0ddb0c198822682
    a4dab739a780a38c5263b02a670a1d0d009f829e
    d6a963e911b8456c06dceb5ee3cc88a70c08bf82
    aa5b6588292e804557c7ff7f24a88f0ea97acca8
    1a2df89c05d33495d7e057dcdf0714d05beb1fc8
    7119e29cb535426c587eaf2cfc2cfcd11a422df0
    2f013887c20310c522f9494ed854554e6f8c7aa4
    a51469326e84ed977ecc4e57fd3d46cdc21aa08f

Change-Id: I50439ced3adec1e6befcb7cb65fe558852f2611a