Sync log and processutils from oslo

This is mainly to pick up two changes in processutils:

85f1784 Move nova.utils.cpu_count() to processutils module
cdcc19c Mask passwords that are included in commands

Commit cdcc19c touches the log module so when copying processutils over
we also copy log, otherwise no other dependencies are copied.  Going
through the commit history on both and the diff from nova, there are no
other commits sync'ed over that require changes to other dependent
modules.

Commit 85f1784 is targeted so we can remove the redundant code from
nova.utils.

Changes:

processutils
------------
85f1784 Move nova.utils.cpu_count() to processutils module
cdcc19c Mask passwords that are included in commands
8a0f567 Remove str() from LOG.* and exceptions
51778f9 Allow passing environment variables to execute()

log
---
109e325 Use oslo.messaging to publish log errors
de4adbc pep8: fixed multiple violations
eac71f5 Fix common.log.ContextFormatter for Python 3
d78b633 Fixes a simple spelling mistake
621d831 always log a traceback in the sys.excepthook
90ae24b Remove redundant default=None for config options
af36c2a Fix logging setup for Python 3.4
cdcc19c Mask passwords that are included in commands

Partial-Bug: #1320028
Related-Bug: #1333370

Change-Id: I8d12661782e8ad065b01aa582e42c142cc2f4076
Merge "Sync log and processutils from oslo"